U. S. B. F. — Doc. 949. 



Fig. 15.— Whitefish esg, 43 days old, showing Fig. 16.— Wliiteflsh egg, 90 days old, showing embryo, 



embryo. 



Fig. 17.— Whitefish egg, yolk sac ruptured by rough Fig. is.— Wliiteflsh egg with triple disks 



handling, 24 hours old. 



DEVELOPMENT OF THE WHITEFISH EMBRYO. 



