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BULLETIN OF THE BUREAU OF FISHERIES 
Figs. 13-19. — Development of the larva of the white sucker, Catostomus commersonii. Cross 
sections through a larva of 8 millimeters. 13. Olfactory placodes. 14. Eyes and otocysts. 
15. Region of the branchial clefts. 15. Ventral aorta and pericardial cavity. 17. Heart. 
18. Body and yolk sac. 19. Cloaca region. The Wolffian ducts are seen joining the intestine 
