Cope.] "^-^O [April 15, 



EXPLANATION OF PLATES. 



Plate I. 



Bones of Typothorax coccinarum Cope, two -fifths natural size. 



Fig. 1. A rib, from below. 



Fig. la. The same with dermal bone, edge view. 



Fig. \h. The same, view of fractured extremity. 



Fig. 2. Another dermoosseous band, one end wanting, from above. 



Fig. 3. Femur, right side, from behind. 



Fig. 3o. Do., proximal view. 



Fig. 3&. Do., distal view. 



Plate II. 



Casts of brain- cases of Belodon buceros and Alligator mississippiensis, 

 natural size. 



Figs. 1-3. Belodon buceros. 



Figs. 4-5. Alligator mississippiensis. 



Fig. 1. Left side. 



Fig. 2. Superior surface. 



Fig. 3. Front view. 



Fig. 4. Left side. 



Fig. 5. Front view, 



RE. Rhinencephalon. 



PE. Prosencephalon. 



ME. Mesencephalon. 



Ep.E. Epencephalon (Cerebellum). 



MO. Medulla oblongata. 



Ep. Epiphysis. 



Hyp. Hypophysis. 



ii. Optic nerve ; v. Trigeminus ; vi. Abducens ; viii. Facialis ; viii. Audi- 

 torius. 



OP. Orbitopineal process or nerve. 



