Bull. U. S. F. C. 1895. The American Lobster. (To face pajje 206.) 



Plate G 



Cdt23. — Egg willi about 32 yolk segments present, seen 

 from vegetative pole. About twenty-eight hours after 

 fertilization. At 12.05 p. m. the nuclei were dividing, 

 and at 2.05 p. in. corresponding segmentation furrows 

 in the yolk had appeared. 29 diameters. 



Cut 24. — Reverse side of same egg, showing divided 

 nuclei at the animal pole. Drawings from living egg. 

 29 diameters. 



Cut 25.— Surface view of embryo 8 days old in invagina- 

 tion stage, showing pit at surface, embryonic area, and 

 mass of in-wandering cells which penetrate deeply into 

 the yolk. These appear now as a dense pear-shaped 

 (hmd when seen through the superficial parts. 29 di- 

 ameters. From No. 3 (1), table 18, July 9, 1890. 



Out 26. — Surface view of egg in invagination stage. Pit 

 very distinct, transversely elongated, showing tendency 

 to become horseshoe-shaped. 29 diameters. Embryo 

 about 8 days old. August 12, 1892. 



Drawn hij F. H. Herrick. 



