382 



WALTER E. CAMP 



The right suprapericardial body in the 47.3 mm. embryo 

 (S. C. 11) is shown in figure 23. It consists of an expanded 

 vesicle attached to the pharyngeal wall by a solid connecting- 

 stalk. Its external form is very similar to that found in the 

 left gland in the 28 mm. embryo (fig. 21). The left body is 

 shown in figure 24. At this stage of development, the gland has 

 become divided into three distinct parts. The dorsal part (.4) 



Ops. 



Fig. 4 Ventral view of a wax reconstruction of the caudal half of the pharynx 

 of an embryo 47.3 mm. long (S. C. 11). X 18. IV to VI, fourth to sixth gill- 

 pouches; Oes., oesophagus; R.s.b-L.s.b., right and left suprapericardial bodies. 



consists of a single isolated tubule broadly attached to the pha- 

 ryngeal epithelium. It contains a small lumen which communi- 

 cates with the pharyngeal cavity. The medial portion of the 

 gland (B) is a longitudinally directed tubule which is bifurcated 

 at its cranial extremity. Its upper or dorsal surface is in con- 

 tact with the tubule (A) but does not fuse with it. Its lower 

 surface is in contact with one of the tubules of the ventral por- 

 tion of the gland. Their epithelial walls are shown fused in 

 only one section of 12 ^. The ventral portion of the gland is 



