A dorsal view of the brain is shown in Figure 30, A. The most prominent structures here seen are the cerebral hemispheres, VH, whose combined transverse diameter is greater than their longitudinal. The tapering, cephalic end of each hemisphere forms an olfactory tract, I, which extends cephalad to form the olfactory bulb, B. ol. Lying between the caudal ends of the hemispheres is a small conical body, G.p., called by Bronn and others the pineal body. The writer has found (62), however, that this body is the paraphysis rather than the epiphysis. Caudad to the cerebra-hemispheres and in contact with them are the optic lobes, MH; they have about the same shape and position as in the frog, but are much smaller in proportion to the size of the hemispheres. Immediately caudad to the optic lobes is the cerebellum, HH, somewhat elliptical in outline as seen from above. Extending caudad from beneath the cerebellum is the medulla, NH, with its triangular fourth ventricle. The outlines of the medulla are somewhat obscured by the numerous roots of the eighth to eleventh cranial nerves, VIII-XI, which arise along its dorsal border. The medulla, as was said above, passes, as is usually the case, without any line of demarcation into the spinal cord, the obex filling in the apex of the fourth ventricle at the anterior end of the median dorsal fissure. [Illustration: FIG. 30. BRAIN OF ALLIGATOR. (A, dorsal; B, ventral; and C, lateral view.) (From Wiedersheim, slightly altered.) _VH_, cerebral hemispheres, each of which gives rise postero-laterally to a hippocampal lobe partially overlying the corresponding optic tract, _Tr.opt_; _ZH_, thalamencephalon; _MH_, optic lobes; _HH_, cerebellum; _NH_, medulla oblongata; _I-XII_, cranial nerves; _1_, _2_, first and second spinal nerves; _B.ol_, olfactory bulb; _Tro_, olfactory tract; _G.p_, paraphysis; _Jnf_, infundibulum; _Hyp_, hypophysis; _Med_, spinal cord.] A lateral view of the brain is shown in Figure 30, C. The hemisphere, VH, is conical in outline, with a small projection from the posteroventral region; its continuation forwards as the olfactory tract, Tro., and bulb, B. ol., is plain. Beneath it and extending forwards are the prominent optic nerve, II, and tract. Caudad to the latter and projecting ventrad and caudad are the infundibulum, Inf., and hypophysis, Hyp.