CHAPTERS XV. & XVI. 

 Tab. XXX. 



Fig. 1. Is the fore extremity of the mole; a, the os humeri, is pe- 

 culiar, not only for its shortness, but in being artici^lated by &, one 

 head to the scapula, and by c, another to the clavicle ; it is altogether 

 of such a nature as to turn the palm outwards for working. 



The foot, or we may name it the hand, has eleven bones in the 

 carpus or wrist, which is two more than in the carpus of man. One 

 of which, d, is remarkable, and from its shape is called the falciform 

 bone; it gives the shovel form to the hand. 



Fig. 2. The head of the Elephant. 



Fig. 3. and 4. The digitated extremity of the proboscis. 



Fig. 5. A transverse section of the proboscis, showing, a, a, the two 

 tubes or nostrils. Between the external integum.ents and the tubes 

 are two sets of small muscles ; an inner one running in a transverse, 

 and an outward one in a longitudinal direction : h, h, the transverse 

 faciculi of muscles, some of which run across the proboscis, others in 

 a radiated, and some in an oblique direction : c, c, the radiated, and d, 

 d, the oblique fibres approximate the skin and the tubes, without con- 

 tracting the cavity of the latter. The others, which pass across the 

 proboscis, contract both the surface of the organ, and the canals it 

 contains ; they can, at the same time, elongate the whole or a part of 

 it : e, e, the longitudinal faciculi, forming four large muscles, which 

 occupy all the exterior of the organ. 



Fig. 6. The extended wings of the Jaf. Ostrologically considered, 

 they are hands, the bony stretches of the membrane being the finger 

 bones extremely elongated : a, a, the thumb, is short, and armed 

 with a hooked nail, which these animals make use of to hang by, and 

 to creep. The hind feet are weak, and have toes of equal length, 

 armed also with hooked nails ; the membrane constituting the wing, 

 is continued from the feet to the tail. 



Fig. 7. The upper mandible of the parrot, which is articulated with 

 the cranium by an elastic Ugament, admitting of a considerable degree 

 of motion. 



Fig. 8. An eye compounded of a number of lenses. The eyes of 

 insects differ widely from vertebrated animals, by being incapable of 

 motion ; the compensation, therefore, is a greater number of eyes, or 

 an eye compounded of a number of lenses. Hook computed the 

 lenses in a horsefly to amount to 7,000, and Leuwenhoek found the 

 almost incredible number of 12,000 in the dragon-fly. 



Fig. 9. The eyes of a spider, drawn from nature. The number of 

 eyes in insects varies from two to sixteen. The spider here referred 

 to answers the description of the garden spider, {Epeira Diadema,) 

 the eyes of which are planted on three tubercles, four on the central 

 one, and two on each side of the lateral ones. 



