Wiuiams. — Eye of Flounder. 
Fig. 18. 
Fig. 19. 
Fig. 20. 
Fig. 21. 
PLATE 4. 
(Pseudopleuronectes americanus.) 
Anterior face of a cross section through the head of a fish of Stage III. 
x 100. . 
Norte. — ob. inf. s. should have been obl. inf. s. 
Portion of a slanting cross section through cerebral lobes and dienceph- 
alon. XX 100. 
Nore. —The letters n. opt. s. in this figure should be changed to tr. opt. dx. 
Frontal section through habenule and geniculate bodies. > 100. 
Parasagittal section through geniculate body and optic tract. X 100. 
