Williams. — Ej-e of Floimder. 



TLATE 5. 

 ( Pseudoplcuronectes americanns.) 



Fig. 22. Diagram of parasagittal section of tectum. X 67. 



Fig. 23. Portion of a parasagittal section of tectum from the anterior p;irt of tlic 



optic ventricle to tlie surface. X 223. 

 Fig, 24. Cross section of optic nerve. X 50. 

 Fig. 25. Parasagittal section of diencephalon and part of metcnceplialon. X 18. 



