Theories of Race

Julien-Joseph Virey, Samuel Thomas von Soemmering

  • Julien-Joseph Virey's portrait

    Julien-Joseph Virey


  • Samuel Thomas von Soemmering's portrait

    Samuel Thomas von Soemmering



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Like many others who became interested in the subject of race, Julien-Joseph Virey was a man of broad interests. He wrote voluminously on pharmaceutical science and technology, philosophy, anthropology, psychology, “magnetic medicine,” the status of women, and social hygiene. He was a pioneer in “chronobiology,” the study of what are now called Circadian rhythms, the bodily cycles controlled by the body’s internal mechanisms and influenced by, for example, the alternation between day and night.

More significantly, Virey was an early pre-Darwinian proponent of the idea that human beings had evolved out of apes through a purely naturalistic process. A rationalist, scientist, and a political progressive in some respects—he occasionally voiced opposition to the slave trade—Virey published Histoire Naturelle du genre humaine (Natural history of the human species) in 1800 at the age of twenty-five, producing a revised and greatly enlarged three-volume edition twenty-four years later, from which the passages below were translated.

In Virey, we can see the consolidation of the discourse on race over the previous twenty years. Citing Buffon, Blumenbach, White, John Mitchell, Hunter, Long, Cuvier, Samuel Stanhope Smith, Kames, Meiners, Hume, Bory de St.-Vincent, Soemmering, Camper, and others, Virey demonstrates an earnest acquaintance with the emerging field even as he takes the subject in a direction that several of those he cites would have found misguided but which acquired many adherents in the years to come.

A conventional interpretation of the Bible had constrained racial theorizing by forcing thinkers to begin at the beginning—either the original pair of Adam and Eve, or the sons of Noah who had survived the Flood—and to build their accounts of human difference on this basis. For many thinkers committed to the idea of a single human family, the most obvious explanation of observable human differences was climate. But Virey, striking a more modern and scientific tone, discounted climate and focused on recent advances in craniology—the study of skulls, which, since Camper, were widely thought to provide the clearest index of a difference that could be called racial.

Craniology focused on the hard evidence provided by bone—specifically the bone encasing the brain. With the science of race having as it were encircled the brain, racial theorists could postulate differences in intellect, culture, and morality as effects or indices of a durable, heritable set of characteristics independent of climate. For Virey, these differences were so significant that the only explanation for them had to be that white and black people had been produced by profoundly different processes.

To account for the differences among races, Virey suggested that the human species had developed through gradual self-modification or transmutation from primates. The white peoples of the world were those whose ancestors had completed this process, while black people had remained at a level of extreme simplicity that now inhibited the process of self-civilization. In effect, Virey proposes a minimal polygenesis, with two “distinct species,” each with its own subordinate “races” or “branches.” After rehearsing a number of physical differences affecting the “biliary and hepactic system” (which gives Negroes a “frightful energy”), the “lymphatic constitution,” and the level of phosphate and lime in the bones, and drawing inferences from these observations concerning character, culture, and behavior, Virey concludes that the African is “radically different from the European” and “nearer to the brute creation than any other of the human species” (54).

Like some others among the early polygenists, Virey was not, however, fully committed to the proposition that species were fixed and unalterable. The existence of mulattoes—which he called “adulterous mixings,” “bastard, intermediary lineages,” and “unstable”—demonstrated that new races were theoretically possible. And he concurred with the claim he associates with Buffon, that racial crossing improves individuals. Still, he argued that such minglings were typically the result of sexual assault by white slave-owners, and that nature itself was averse to them. “Nature tends to resume its primitive forms,” he said in a chapter on “Mulattoes”; “it does not enter into our criminal connexions” (118).

In the expanded 1824 edition, Virey made his case with a variety of charts, statistics, measurements, and illustrations including the one reproduced below, which suggested a progression from the orangutang to the Apollo Belvedere, passing through an intermediate phase in the Negro. Versions of this sequence would be reproduced in many subsequent publications, including Josiah C. Nott, Types of Mankind (1854). The general model of a linear evolutionary progression from barbaric nature to civilization—the latter often exemplified by Greek sculpture—was to provide an easily-grasped visual argument for many racial theorists in the nineteenth century.

Theoretical conclusions published in a French treatise largely concerned with physical differences and diseases still managed to find receptive readers, especially in the American South. Among them was J. H. Guenebault of South Carolina, who translated, or very freely “extracted,” that part of Virey’s text that applied particularly to Negroes, and published it in 1837 in Charleston, South Carolina, which had at the time one of the largest slave markets in America. His extraction, published with the title of Natural History of the Negro Race, included an extended quotation from Jefferson’s Notes on the State of Virginia that did not make it clear that the words were Jefferson’s and not Virey’s, and even included references to Virey himself that were obviously not in the original. In his “Dedication” to the members of the Literary and Philosophical Society of Charleston, Guenebault condemned the “sad mistake of the natural order of things” that confuses liberty with license and equality with levelling, and apologized for the clumsiness and “incorrect expressions” to be found in Virey’s text. The passages reproduced below are from this publication.

Guenebault included in his publication a translation of parts of Samuel Thomas Soemmering’s 1785 essay “On the Comparative Anatomy of the Negro and European,” which had arrived at some of the same conclusions Virey subsequently reached but had pushed them much farther than Virey. After learned discourses on Negro anatomy and diseases, Soemmering turned to the subject of “Negresses” in an entirely different vein, documenting Negro inferiority in nearly all categories. He concluded his argument by pointing out that while Negroes have often been enslaved, they have never enslaved another race, a fact Soemmering considered confirmation of Negro inferiority. “Negresses” is followed by chapters on Creoles and Mulattoes, a terminal chapter titled “On Slavery,” and several appendices on diseases. The chapter on slavery treats the practice as ancient, God-ordained (through the curse of Ham), a constant feature of history, and entirely natural, as witness the fact “that among several species of animals, the females and young ones obey males” (121).

Natural History of the Negro Race



The features, characteristics, figure and colour of the negro species, are perpetuated in every climate, it does not undergo a peculiar change as long as it is not mixed with any other races. More disposed to sensual affections than to pure contemplations of the mind, the negro has more feelings than thoughts, his intellect is not generally so extensive as that of the white man; his shape even bears some resemblance to the Orang-Outang. Every one knows the projecting face of negroes, their woolly hair, large and thick lips, broad flat nose, retreating chin, round eyes which seem to start out of their sockets, particularities which serve to distinguish them, and would make them easily recognized at the first glance, were they even as white as Europeans. The negro has the forehead lower and rounded, the head compressed towards the temples, teeth set obliquely and projecting, in many of them the legs are bent outwards, the calfs very slender, the knees always half flexed, an awkwardness of gait, the body and neck inclined forwards, whilst the buttocks protrude. Such characteristics show evidently a degradation towards the ape genus, and should their appearance not betray such a degradation, their moral character would show it sensibly.

The black, as it is to be remarked in the ape genus, is an imitator by nature, he acknowledges the intellectual superiority of the white man, is easily reconciled with his servitude, careless and lazy. Such habits indicate a natural and innate weakness of the soul.

We must also remark that negroes, on account of the projection and inclination of their teeth, cannot pronounce the letter R. Such is the case with the Chinese. It is worthy of observation that all those nations are exceedingly pusillanimous; on the contrary, all inhabitants of northern climates articulate this letter with much facility; the sound of it occurs frequently in their languages; they are brave and courageous. The letter R is to be found in almost all oaths which express anger and passion; its accurate pronunciation results from the vertical position of the teeth, and the small projection of the jaws; for, in proportion, as the latter become smaller, the forehead is more prominent, the brain expands and increases, the natural dispositions acquire more energy, and the soul more activity. Hence, it follows, that the negro is in some respect by his form, the capacity of his skull, the weakness and degradation of his mind, the reverse of the European. (1-3)

In Africa, negroes lead a precarious life. . . . No wonder if the greater part of those tribes, addicted as they are to war, devastation and plunder, are reduced to the utmost state of barbarism, and vie with each other in cruel reprisals, as several examples are to be met with of a like nature among savages in the forests of America.

Generally, the negro is of a merry disposition, even in servitude, and sings an insignificant air with a monotonous voice. If he only hears the sound of a tam-tam (a kind of tamborine) or the harsh noise of the balofo, &c. he leaps for joy, and begins to dance. All his body is agitated with pleasure; each muscle quivers; his motions are animated by love, his gestures become lascivious, and express the violent ardor which excites him. The negress partakes of these affections: she adorns her head with a red handkerchief, rubs with oil her shining skin, and encircles her neck with red seeds. All negro women have large, flaccid and pendulous breasts; this peculiarity is common to all the black race, as it is also to the Mongole. In the Lapland, Greenland, Calmuc, Hungarian, and Morlychian women the breasts are likewise pendulous, and the nipples of a blackish color — therefore, such a conformation is not the effect of heat alone (though it contributes much to it) but the natural constitution of those races, in whatever climate they live.

Negresses are good nurses, breed much, and are very lascivious as well as negroes. At twelve years of age, they are ripe for marriage. This fact is also remarkable in the Mongole race, in both the north and south of Asia; but they show early marks of old age, and are polygamists. (5-6).


A more projecting mouth, a face of a triangular and pointing shape, a facial angle of about 75 degrees, a brown skin, eyes at a great distance from each other, and always half shut, a nose entirely flat, and very broad, lips thicker than those of negroes, hair like flocks of wool, and knotty, very prominent cheek bones, and a forehead exceedingly flat, are characteristics by which we distinguish this race from the blacks, or that of negroes and Caffres. [footnote: “The true negro is of a deep shining black—the Caffre of a yellow copper color, with long woolly hair.”]

In most skulls of Hottentots, which have been examined, the occiput is pointed, so that the back part of the head is narrow, precisely the reverse of European and Calmuc skulls. . . . Their natural disposition is very stupid; their minds incapable of the smallest conception; they are more lazy and careless than any of the human species; they are timorous, but fight desperately among themselves when determined. Nothing can surpass the imbecility of this good natured people; in capable of an atrocious crime, their weakness of character prompts them to yield to oppression; but Hottentots are not good slaves, for they prefer death to long hard labour, and in as much as they remain indifferent to the wants of domestic life, they are inclined to all brutal passions, to dancing, lust, drunkenness, gluttony, sleep, & c. They appear to be altogether “corporeal,” having scarcely a notion of a superior being, and no idea embodied with any but carnal pleasures. There is but one step between their intellect and that of the orang-outang; in short, they lead an animal life. . . .

The constitution of Hottentots is extremely weak, or lymphatic; their joints are small; their antipathy to work very great; the iris of their eyes is of a chesnut color; their eyelids are drawn up obliquely, like those of the Chinese, although their sight and senses are perfect. They prefer idleness even to pleasure, and in the opinion of Hottentots, “'to think is to work, and all work is the plague of life.” . . .

Nothing can be more stupid and filthy than a Hottentot. Always greased with a mixture of tallow and soot, or covered with cow dung, they wear as bracelets, straps cut out of a raw skin, which they allow to rot on their bodies; they never wash the bowels of animals, which they eat raw. (10-12)


In whatever light we consider Negroes, we cannot deny that they present characteristics of a race distinct from the white. This truth, grounded upon incontestable facts of anatomy, is universally acknowledged. Now, in natural history, that which distinguishes a species from a race, is the permanency of characteristic features, notwithstanding contrary influences of climate, food, or other external agents: whereas, races are but varied modifications of a sole and primordial species.

All the facts which have been collected, concur to prove how constant and indelible are the natural and moral characteristics of negroes in every climate, notwithstanding a diversity of circumstances. In natural history, it is then impossible to deny that they form not only a race, but truly a species, distinct from all other races of men known on the globe. (19)

The brain, which in white men is gray or ash-colored, on its exterior or cortical part, is especially black in Negroes. Their medulla oblongata presents a yellow gray color, and the striated bodies have a brown hue.—Their bile is also of a darker shade than in whites; the Negro, therefore, is not only black on his exterior, but is so in the inward parts of his body, even the most interior. . . . Soemmering and Ebel, learned German anatomists, have proved that the brain of the negro was comparatively narrower than that of the white, and the nerves on the base of the brain, larger in the former than in the latter. Several other observers have remarked that in proportion as the face of the negro protruded, his skull lessened. This gives a difference of a ninth more between the capacity of the head of a white, and that of a negro. . . .

Very important reflections arise from these remarks on the proportions between the skull and face of the negro, and the comparative volume of his brain and nerves. Indeed, the more an organ extends, the more powerful and active it becomes; in like manner, the more it contracts, the more it loses its activity and power. Hence it follows, that if the brain contracts, and the nerves emerging from it expand, the negro will be less inclined to think than to abandon himself to sensual pleasures, whilst the reverse will be remarked in the white. . . . [The negro] lives only by sensations. Every one knows that they have a piercing sight, an acute smell, very delicate ears for music; a sensual taste, and that almost all of them are gluttons. They feel keenly the power of love; in short, they are superior to all other men in agility, dexterity, imitation, as respects the body. . . . Their feats of agility are surprising. They climb, vault on a rope with wonderful facility, equalled only by monkeys. . . . When dancing, negresses set in motion, at the same time, every part of their body—they are indefatigable in it. . . .

If we find fewer moral relations among negroes, such as arise from the mind, thought, knowledge, religious and political opinions; in return, they have more natural relations; their affections are more readily communicated; they are more easily impressed by the same feelings, more subject to emotions; they share in a moment the feelings of their black fellow-men, and take instantly their part. (23-27)

Although it appears unjust in some respects to trace out the limits of the mind, yet, it is the duty of a naturalist to examine thoroughly, so important a question. Hume, Meiners, Soemmering, and many others have maintained that the negro race was very inferior to the white, as to the mind. Their opinions agree with the observations of the distinguished anatomists Cuvier, Gall, Spurzheim, and Dr. Virey, since the cerebral capacity of all negroes who have been examined is generally smaller than that of whites. — Blumenbach remarked that the skulls of Calmucs, or the Mongrul race, and of Americans, (although smaller than Europeans’) were still larger than those of Africans. But independently of this fact so well proved, and the stamp of which is apparent on the depressed forehead of the negro, let us consult the history of this species on the whole earth.

What kind of religious ideas has he been able to form by himself on the nature of things? This question is the surest way to appreciate his intellectual capacity: we see him kneeling before roughly carved idols, worshiping a snake, a stone, a shell-fish, a feather, &c. . . .

In reference to social industry, they never made by themselves any conquest. Did they ever build great monuments, large cities, as the Egyptians did, even to shelter themselves from the heat? Are they protected from the sun by light tissues, as the Indians? No huts, or the shade of palmetto trees are sufficient for them. Can they beguile by arts or inventions, the tedious hours they spend in laziness on so rich a soil? No, they do not even possess the ingenious game of chess invented by the Indians, or those beautiful tales produced by the fruitful and lively imagination of the Arabians. Negroes living in the vicinity of Moors and Abyssinians, nations whose primitive race was white, are despised by them as stupid and incapable. How often are they deceived in commercial exchanges? They are oppressed, subdued in the very presence of their own countrymen, who have not sense enough to unite in strong bodies to resist and to form regular armies. They have thus been always conquered by Moors, and obliged to give way to them. They know of no other fabrication of arms but the “zagies” and arrows, poor weapons to oppose to the sword, cannon and powder.

In their languages, so limited and abounding in monosyllables, terms are wanting to express abstractions; they cannot conceive any thing but what is material and visible; so, they do not pry into the future, and forget very soon the past. No historical records are to be found among them. They do not even possess hieroglyphics: the alphabet has been taught to many of them, and yet their languages hardly present any grammatical combinations.

Their music has no harmony, though they appreciate and feel it; it consists only in a few loud intonations, and cannot form a train of melodious modulations. Their senses are perfect, yet they want the attention by which they are displayed, and that kind of reflection by which we are induced to put objects into comparison, in order to establish relations between them, and to observe their proportions.

As long as negroes will not become civilized, by their own exertions, as did the white race, some private examples of remarkable intellect among them, (such are mentioned by authors,) will only prove exceptions. Time and space have not been wanting to the African, yet he remains in a stupid and brutish state; whilst the other nations on earth have approached more or less to social perfection. No political or moral cause of the same nature to that which bends the minds of the Chinese, can prevent the improvement of the negro in Africa. This climate has assisted the extension of the intellect among the Egyptians of old: we must then conclude, that the constant inferiority of the minds of negroes, results only from their conformation; for, in the Islands of the South Sea, where they are to be found mixed with the uncivilized race of Malays, they stand inferior, although they have not been conquered by them. . . .

Every thing serves to prove that negroes form, not only a race, but a distinct species, from the beginning of the world . . . .

Negroes are exceedingly simple [in French: “grands enfans,” or large children]. As we have said, no laws nor fixed governments are to be found among them; every one lives as he pleases, and he who apparently displays more intellect, or is richer, becomes judge of every quarrel; he is often made a king; but his royalty is a mere shadow; for, although he may sometimes oppress, enslave, sell and kill his subjects, yet the poor fellows have no kind of loyalty towards him . . . being very vain, they like to be distinguished by ornaments; they have created ranks among themselves; they are exceedingly fond of feasts and ceremonies, and wish to appear with magnificence. . . .

Negroes cannot be managed, except by captivating their senses with pleasures, or striking their minds with fear. They work only through necessity, or when compelled by force. Satisfied with little, their industry is limited, and their genius paralyzed, because they are not tempted by any thing but what satisfies their sensuality, or their natural desires. Their character being more indolent than active, they seem to be more fitted to be ruled, than to govern, in other words they were rather born for submission, than dominion. Moreover it is very seldom they know how to command; for it has been observed, that when they have power, they are capricious tyrants. This last character does not apply only to negroes; experience has taught us that the most tractable slaves, become always in every country the worst masters, because they wish to be indemnified in some measure for what they have suffered, by inflicting pain on others. (33-39)

Transformation Image
Duhamel, “the facial angle of species,” in Julien-Joseph Virey, Histoire naturelle du genre humaine, Paris, 1801, t. 2. Not reproduced in Guenebault.

“On the Comparative Anatomy of the Negro and European”


Included in this volume is a translated selection from Samuel Thomas Soemmering’s Ueber die Körperliche, Verschiedenheit des Negers von Europäer (1785). In this selection, Soemmering, who would become a respected physician, professor of anatomy, inventor, counselor to the court of Bavaria, and a widely celebrated European intellectual, describes in detail the differences between Negro and European bodies, and skulls in particular, with Greek statuary and apes providing further points of comparison. His essay is a particularly striking and extreme instance of the connection between physiology and intellect that Virey endorsed. 

1. In a conversation with Professor Lichtenberg on this subject of this Essay, he, says Professor Soemmering, with great acuteness, directed my attention to the manner in which the connexion is made between the head and trunk in the negro and European. In the former (as if a portion of the hind part of the skull were removed) the depression between the head and shoulders is much less considerable; a conformation exhibited by animals of the ape tribe in a still more remarkable degree.

2. In the Negro, the aperture of the eye-lids is smaller than in the European; and of course less of the eye is visible. The eye-ball is perhaps larger; a blackish ring about half a line in breadth, surrounds the corner; and the albuginea (as in some apes) instead of a pearly white, is of a dirty yellow color. . . .

III. The nose is flat, short, and disproportionably broad; and may be said to lie on the upper lip, rather than to project over it. Its extremity is obtuse, and turned upwards. The nostrils are wide.

IV. Although the Negro’s lips are large and turgid, and incline more to a bluish black than to a dirty rose-color, they afford an obvious and decisive characteristic, which distinguishes him from all animals of the ape genus. For Nature has refused lips to every animal of that tribe, without an exception in favor of the orang-outang, who has no farther claim to a pre-eminence than what is conferred by the caprice of artists. . . . .

V. The ear is of a more circular shape than in Europeans; and resembles, somewhat more closely, the same organ in apes. It seems frequently to project farther than usual from the head. It is a well-known fact, that savages can move their ears at pleasure, and possess the sense of hearing in great perfection.

VI. To those who have frequent opportunities of seeing Negroes, it may seem superfluous to remark, that the relative proportion of the features hitherto described, differ widely in different individuals: and form as great a variety of physiognomies as prevails in Europe. The feature of some Europeans are not unlike those or negroes. A person of this description lives in my neighborhood; but his mother, it must be confessed, was suspected of improper intercourse with an African. . . .

VII. The jaw bones and the cavities which contribute to form and to protect the organs of sense (whether considered absolutely, or with a reference to the rest of the head) are constructed on a larger scale in the negro; and are probably better adapted to their office than in those tribes of mankind in whom a superior understanding supplies the imperfection of mere animal accomplishments.

VIII. Camper has proved, agreeably to the principle of his facial line, that, in the finest Grecian relic of ideal beauty, the bones of the head are in the largest, and those of the face in the smallest possible proportion. The brow advances to a line with the nose, mingles with the arch of the head, and, like the occiput, is lost a gentle curve:— a conformation eminently fitted to provide an ample space for the brain.

IX. In the construction of the negro’s skull, which is low and flat, both behind and before, nature seems almost to have reversed the proportions of her favorite model. Were we to compare two skulls, in which the distance between the root of the nose and the alveoli was equal, we should find the os frontis longer in the European than in the negro. The depression between the superciliary arches is tolerably well expressed on the skull of an old negro in my collection, though wanting in one of Professor Blumembach’s specimens. . . .

X. The Negro skull, viewed in front, appears to be compressed at the sides, especially at the upper part; its cavity seems to be straiter; and the parietal bones smaller in every dimension, than in European skulls. In some of the finest specimens of mummies, according to Blumenbach, the head is still more compressed than in the Negro. (57-61)

Negroes and Negresses both exhibit great lasciviousness, though the latter carry it to an extent unknown in our climates, a characteristic which may be deduced from some peculiarities of structure, as well as from observation. It is this temperament which is supposed to render them attractive in the eyes of Europeans, when the disgust which at first arises wears off. . . .

In several countries of Africa, the time of puberty is very early and corruption is carried to a monstrous excess. Among the inhabitants of Darfur incest is very common, and chastity is considered as the result of ugliness or inferiority, prostitution being received as a proof of worth. (88-89)

Although the extreme lasciviousness of negro women opposes the propagation of the human species, yet their fecundity is undoubtedly augmented by their simple and animal mode of living: for it has been asserted that the more men and women are civilized, and cultivate their mind and intellect, the more unfit they become to propagate. Almost all the vital power is carried to the brain and senses at the expense of the other organs. (94).

When nature made the negro inferior to the white man in intellect, it indemnified him in another way. If we enjoy greater pleasures from the mind, Africans are more pleased through their senses. Our greatest delight consists in towering to high thoughts, acquiring knowledge, and enjoying the charms of social intercourse. Negroes find their greatest pleasures in being devoted to material objects. If we seek after glory, riches, power, they on the contrary, prefer an indolent obscure life, and believe that riches cannot make up for any sacrifice; to work is more intolerable to them than misery; they do nothing, unless compelled by necessity. A European must have wealth, consideration, a thousand objects of luxury, or particular comfort —his whole life is spent in seeking after enjoyment, and still he is never satisfied. A negro, on the contrary, lives on, without attempting to better his condition. He would rather forego any thing that might benefit him, than take the trouble of procuring it, and is satisfied in his nothingness. We require excitement; the negro rest. What constitutes our pleasures, are his troubles; and that apathy, which is a suffering to us, is to him a source of the greatest delight.

Let the white man study the celestial bodies, and rate their course; let him travel over the globe, to discover the mysteries of nature; and the Almighty’s nameless and stupendous works—the dull Hottentot stretches himself on the ground, smokes his pipe, eats and sleeps; he laughs at our activity, which he calls folly and excessive misery; he thinks we are pursued every where by the demon of necessity. . . .

We see very evidently, from the narrowness of his brain, that the intellect of the negro is not so active as ours. Even the savages of Florida, and Carribeans, reduce to slavery all the negroes they have carried off from European settlers. All over the globe, negroes in the vicinity of another human race, are very soon subjected. On the contrary, not one of the other races has ever been enslaved by them. In fact, it would be unnatural to suppose that the less intelligent should rule. This alone proves the constant inferiority of the negro species among all other races. (97-98)

If man exists by the intellectual faculties, the negro beyond doubt will, on that account, be an inferior man; he will approach nearer to the brute, as we see him more subject to the wants of his stomach, and to all sensual gratification, than to the dictates of his reason. He does not love his idols, but he worships them through fear. Such a degradation is still more apparent in the Hottentot; no human being can be more stupid, brutal and dull than he is. If we compare him with the most perfect monkeys, the distance between them will appear comparatively trifling, and he is next to them in his organization; witness the grinning projecting mouth of the Hottentot, the small size of the internal volume of brain, the posterior position of the occipital hole, the inflexion of his dorsal vertebrae, his pelvis also in an oblique position, the curve of his stomach smaller, his knees half bent, the distance between his toes, and the flat position of the soles of his feet as in monkeys. The Hottentot feels a difficulty in speaking; his voice is like the clacking of a turkey, and presents an evident affinity to the Orang-Outang, which has a kind of hollow clacking, owing to the membranous bags of the larynx in which his voice is immediately lost. (101)

There is a real gradation of organization and faculties in all the bodies of Nature; for we may descend by degrees from the white man to the Negro, and from the Negro to the Hottentot: from the Hottentot to the Orang Outang the transition is very great, as the first among the monkeys is still very inferior to the last among men. From the monkeys we are led by progressions hardly perceptible, to the whole class of quadrupeds; from the latter to birds, reptiles, fishes, molluscas, crustaceous; insects, worms, zoophytes. (103)

Raymond Corbey, The Metaphysics of Apes (Cambridge: Cambridge University Press, 2005). 

Pietro Corsi, “Before Darwin: Transformist Concepts in European Natural History,” Journal of the History of Biology 38 (2005) 1: 67-83.