470 



tr. S. BUEEAU OF FISHERIES 



Fia. 4.— Larval stages of the shad (Alosa sapidinsima) 



P Young fish immediately after hatching, viewed as an opaque object and somewhat obliquely from one 



side, to display the relations of branchial and hyomandibular arches, and position of pectoral fin. 

 Q. Young fish third day after hatching, viewed as a transparent object to show cxtention of segmental 



ductforward; chorda c/i. 

 R. Young fish 5 days after hatching, very much enlarged, and viewed as an opaque object. Only a slight 



remnant of tlie yollc sac F remains. ^ ,. ^ 



S. Young fish 17 days after hatcliing, viewed partly as an opaque and partly as a transparent objex't; py , 



pylorus 4nd rudimentary air bladder above it; /, intestine, filled with the remains of ingested food. 



The opercula are already so far developed as partly to conceal the gills. 



