Chap. XII.] 



BRAIN OF FROG. 



419 



cephalon, or optic tlialami, so called from the fact 

 that when the brain is laid on its upper surface the 

 optic nerves rest on them as on a couch (thalamus). 



Connected with the upper surface of the thala- 

 mencephalon is the pineal gland, which is not 



01 



CH 



Fig. 179. A, Brain of Frog from above ; B, from below. 



1, Olfactory nerves; ol, olfactory lobes; CH, cerebral hemispheres; i-T, 

 lamina terminalis ; T^, thalamencephalon with pineal gland (PG) ; OpL, optic 

 lobes; cl, cerebellum; MO, medulla oblongata ; 2, 9ptic nerves ; OT, optic 

 chiasma ; TC, tuber cinereum ; H, hypophysis cerebri ; 310, cerebral nerves. 

 (After Ecker.) 



nervous in nature, while the lower surface of the 

 same region of the brain is continued into the funnel- 

 shaped tnfoer cinereum (Fig. 179 ; TO), with the 

 base of which is connected the so-called pituitary 

 body; this, like the pineal gland, is not nervous in 



