490 
■T. GRAHAM KEEK. 
At stage XXXVI (text-figs. 3 c and 4 c) the intestinal 
rudiment forms a spirally coiled structure, the turns of the 
Text-fig. 4 
Text-fig. 4 b. 
Text-Figs. 4 a, b, c, d. — Dissections of the mid-o-iit of young Lopi- 
dosirens seen from the dorsal side. a. Stage XXXII. b. Stage 
XXXV^. c. Stage XXXVI. d. Stage XXXVII. c.c. Cloacal 
ciBCum. f.fl. Fore-gut. 1. Lung. li. Liver, m. n. d. Mesonephric 
duct. pa. Pancreas, pa. d. Dorsal iiancreas. p?i. Pharynx, 
sjj. Spleen, t. Tongue. 
spiral being separated by the deep incision mentioned in the 
preceding stage. In all probability this spirally coiled condi- 
