OF VIVIPAROUS VERTEBRATA. 73 



of this description, they are produced by an excretion on the 

 surface of that membrane. 



The mammae, are also absolutely similar to the other glan- 

 dular secretory organs. 



63. The mammalia, however, still present great varieties 

 in their organization; either in the organs of touch, which 

 are the more perfect, in proportion as the fingers are more 

 numerous and pliable, and less enveloped by the nail ; or in 

 the organs of mastication, and consequently in the rest of the 

 digestive organs, or finally, in the organs of generation. The 

 different combinations of these varieties, which occasion many 

 others in all the functions, and even in the intelligence of the 

 animal, have caused this class to be divided into several orders, 

 among which is that of the bimana, formed of one single 

 genus, Homo, or man. 



64. Man is distinguished from the other mammalia, by 

 some slight differences in the vegetative functions, by some 

 others, more important in the organs of the animal functions, 

 but principally by his intelligence. 



Intelligence, which distinguishes man, is characterized, 

 above all, by consciousness, reason and free will, by a moral 

 sentiment, and that of a divine First Cause. 



Besides this, of all the mammalia, man has the hemispheres 

 of his cerebrum and cerebellum, the most greatly developed, 

 and most largely furnished with circumvolutions. This vo- 

 lume of the hemispheres, appears considerable, particularly in 

 comparing it with the medulla, the nerves, the senses and the 

 muscles. His cerebral functions are greatly developed, and 

 very distinct from instinct. He is gifted with speech, and 

 lives in society. He is the only true, two handed, and biped 

 animal; his whole body is organized for a vertical position, 

 and his hands are evidently reserved for other uses, than for 

 standing on. 



The heart is directed obliquely over the diaphragm, and the 

 aorta somewhat differently arranged from that in the quadru- 

 peds. The organs of digestion are fitted for a varied diet, 

 principally vegetable. The penis is free, and without any in^ 



