288 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
EXPLANATION OF PLATE XL. 
Fig. 12. Young sterlet, recently escaped from the egg ; yelk-hag still very large. Total length, 
After W. K. Parker. 
Fig. 13. Young or larval sterlet, somewhat older than foregoing, 6^™“ long. After W. K. Parker. 
Pig. 14. Larval sterlet 9-1“™ long, showing the branchial filaments exposed beyond the membranous 
operculum, the pectoral fin, the young barbels, and the strongly developed teeth with which 
the jaws are armed at this period. After W. K. Parker. 
Pig. 15. Under side of head of larval sterlet 81®™ long, showing the well developed teeth in the jaws 
at this stage, the four rudiments of barbels in front of the upper jaws, and the depression still 
farther forward, which probably answers to the “ suctorial disk ” observed by A. Agassiz and 
Edward Allis in the same region in Lepidosteua and Amia. After W. K. Parker. 
