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Show 48 MAMMALIA. 1 · 'ploon hangs iu front of the large lobes and one small one; us ~pl intestines and extends into the pelvis. To com' plete t 11 e h as t Ys ketch of the anatomical structure . of Man . . t h' . t duction we will add, that he bas thirty-two reqUISite ofr th~Shlll ro belon'g to the neck, twelve to the back, five vertebrre, o w IC seven 1 to the o·m s, fi ve t o the sacrum ' and three to the coccyx. .S even . f h' 'b e united with the sternum by elongated cartilages, - pairs o ISllrid star 'bs • the .five following pairs are denominated and are ca e rue r1 ' . · . . false ones. HI.S a d u lt cranium is formed of e1ght bones; an occ.t pl· . t oris two parietalia, and the frontal, ethmoidal tabs, two ossa emp ' · b and sphenoi'd a1 b one s • The bones of his face a.r e fo. u.r teen m num er, two maXI'1 1 ari•e s, t wo ossa malre ' each of which JOinS the temporal to the maxi'1 1 ary b on e of 1'ts own side by a kind .o f han. dle called the · h. two nasal bones two ossa palatl behmd the palate, zygomatic arc , ' . f · a vomer b e t ween the nostrils' two turbmated bones o the nose m the nostrils, two lachrymals (unguis) in the interna.l angles ?f the orbits and the single bone of the lower jaw. Eacl~ JaW has ~Ixteen teeth; four cutting incisors in the middle, two pomted c~mnes at the corners and ten tuberculated molares, five on each side. At the extremi~y of the spine of his scapula, is a tuber~sity c~lled ~he acrom1· 0n, to whi'ch the clavicle is attached, and over Its a.r ticulatiOn is a point called the coracoid process with which certa1? muscles are connected. The radius revolves upon the ulna, owmg to. the mode of its articulation with the humerus. The carpus has ei~ht bones, four in each range; the tarsus has seven; those of the rematn· ing parts of the hand and foot may be easily counted by the number of fingers and toes. . Enjoying uniform and regular supplies of nourishment, the ~r~1t of his industry, Man is at all times inclined to the " pl~Ism d'amour," without ever experiencing that irresistible ~nd v1olent impetus which marks the passion in quadrupeds. His orga~ ~f generation is not upheld by a bony axis; the prepuce does not tie. It down to the abdomen, and it hangs loosely in front of the pubts. Numerous and large veins which effect a rapid transfer of the blood of his testes to the general circulation, appear to contribute to the moderation of his desires. The uterus of woman is a simple oval cavity; her mammre, only two in number, are placed upon her breast, and correspond with the facility she possesses of supporting her child upon her arm. Physical and Moral Development of Man. The term of gestation in the human species is nine months, and but one child is usually produced at a birth, as in five hundred 1UMANA. 49 cases of parturition there is but one of twins; more than the latter is extremely rare. The fretus, a month old, is generally about one inch in height; when two months, it is two inches and a half; when three, five inches; in the fifth month, it is six or seven inches; in the seventh, it is eleven inches; in the eighth, fourteen, and in the ninth, eighteen inches. Those which are born prior to the seventh month usually die. The first or milk teeth begin to appear in a few months, commencing with the incisors. The number increases in two years to twenty, which, about the seventh year, are successively shed to make room for. others. Of the twelve posterior molares which are permanent, there are four which make their appearance at four years and a half, and four at nine; the last four are frequently not cut until the twentieth year. The growth of the fretus is proportionably increased as it approaches the time of birth-that of the child, on the contrary, is always less and less. It has more than the fourth of its height when born; it attains the half of it at two years and a half, and the three-fourths at nine or ten years; its growth is completed about the eighteenth year. Man rarely exceeds the height of six feet, and as rarely remains underfive. Woman is usually some inches shorter. Puberty is announced by external symptoms, from the tenth to the twelfth year· in girls, and from the twelfth to the sixteenth in boys,; it arrives sooner in warm climates, and neither sex, (very rarely at least,) is productive before or after that manifestation. Scarcely has the body gained the full period of its growth in height, before it begins to increase in bulk; fat accumulates in the cellular tissue, the different vessels become gradually obstructed, the solids become rigid, and, after a life more or less long, more or less agitated, more or less painful, old age arrives with decrepitude, decay, and death. Man rarely lives beyond a hundred years, and most of the species, either from disease, accident, or old age, perish long before that term. The child needs the assistance of its mother much longer than her milk, from this it obtains an education both moral and physical, and a mutual attachment is created that is fervent and durable. The nearly equal number of the two sexes, the difficulty of supporting more than one wife, when wealth does not supply the want of power, all go to prove that monogamy is the mode of union most natural to our species, and, as wherever this kind of tie exists, the father participates in the education of his offspring, the length of time required for that education allows the birth of others-hence the natural permanence of the conjugal state. From the long period of infantile weakness springs domestic subordination, and the order of society in general, as the yo'u.ng people which compose the new Vo~. 1.-G ., |