586 KEPORT OF COMMISSIONER OF FISH AND FISHERIES. [130] 



EXPLANATION OF PLATE V. 



Fig. 24. Tail of embryo cod on the thirteeutli day, viewed from below, showing the 



position of the yelk blastopore bl. x 5.5. 

 Fig. 25. The same seen somewhat obliquely from the side, with the chorda dorsalis 



shining through. 

 Fig. 26. Embryo cod fourteen days old, seen from below, x 55. 

 Fig. 27. Head of an embryo eleven dg^s old, viewed from above, nearly as far advanced 



as Fig. 26, in optic section, showing the structure of the head, x 150. 

 Fig. 28. Head of embryo seventeen days old, from the side, showing the lumen of the 



heart h, the nasal and auditory vesicles, the vesicles of the primary di- 



A'isions of the the brain, lateral longitudinal fold^of the right side, which 



develops into the pectoral or breast iin. 

 Fig. 28 a. Tail of an embryo cod, looking nearly at its end, showing the ])]astopore 



II and the lumen of Kupffer's vesicle kv. x. 55.. 



