518 MANUAL OF ZOOLOGY SECT. 



features are to be seen when a comparison is made with the 

 pigeon. In the eye, the sclerotic is composed entirely of 

 dense fibrous tissue ; the pecten is absent. In the ear the 

 principal point of difference is in the special development 

 of the cochlea. This part of the membranous labyrinth, 

 instead of retaining the simple curved form which it pre- 

 sents in the bird, is coiled on itself in a close spiral of two 

 and a half turns. 



FIG. 311. Lepus cuniculus. Longitudinal vertical section of the brain (nat. size). 

 Letters as in the preceding figure; in addition, cb, cerebellum, showing arbor 

 vitse; c. c, crus cerebri; ch l , parencephalon; cA 2 , temporal lobe; c. ma, corpus 

 mammillare; _/. m, foramen of Monro; in/, infundibulum; iy, lyra; m. o, me- 

 dulla oblongata; o. ck, optic chiasma; olf, olfactory lobe; pty, pituitary body; 

 vl. tp, velum interpositum; v. vn, valve of Vieussens; //, optic nerve. (From 

 Parker's Zootomy.} 



The special features of the middle ear with its auditory 

 ossicles have been already referred to. 



The kidneys are of somewhat compressed oval shape, 

 with a notch or hilus on the inner side. They are in 

 close contact with the dorsal wall of the abdominal cavity, 

 the right being somewhat in advance of the left. Towards 

 the hilus the tubules of the kidney converge to open into 

 a wide chamber, the pelvis, which forms the dilated 

 commencement of the ureter. When the kidney is cut 



