THE HYPOPHYSIS IN REPTILES 255 



Inasmuch as my results for alligators by Brum's method did 

 not bear out Bruni's conclusions for amniotes, his method was 

 applied to turtles and lizards. The stalk of a 14.5 mm. turtle 

 is slightly caudal to that of a 9.2 mm. embryo. The hypophysis 

 of a 9.2 mm. turtle is dorsal to that of the others. In lizards 

 the hypophyseal stalk of a 15 mm. embryo is caudal to the 3 

 and 9 mm. stages and the hypophysis more dorsal. The caudal- 

 ward shifting of the axis of the hypophyseal stalk in turtle and 

 lizard embryos is similar to that described by Bruni in Gongylus. 



c } A 



Fig. 51 Drawings of hypophyses of the same alligator embryos as in figure 

 50. A,V2 mm. (R. C. 27); B, 22 mm.; C, 120 mm. (W. U. C. 176, 178); x-y, base 



line. 



It is possible that older embryos, in which the stalk has dis- 

 appeared, might show a later cranial shifting. 



HISTOLOGY OF THE HYPOPHYSIS 



All of the adult animals studied were obtained between the 

 months of October and May, except a few lizards which were 

 collected personally. These specimens, with the exception of 

 the alligator, were killed at once and were fixed immediately 

 in 10 per cent formalin or in Zenker-formalin. In the following- 

 description the various stains used are indicated. 



