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WALTER E. CAMP 



acini. The entire gland is small and lies very close to the 

 pharyngeal wall to which it is attached by its excretory duct. 

 There is no evidence of secretion in the gland at this stage. 



TOPOGRAPHY AND MORPHOLOGY 



The suprapericardial body or gland in Acanthias first appears 

 in embryos of about 20 mm. in length. Although it is occa- 

 sionally present later on both sides of the pharynx, its early 

 appearance is always limited to the left side. The gland on 

 the right side does not make its appearance until about the 

 33 mm. stage. The anlage of the gland appears as a simple 

 e vagina tion or outpouching of the epithelium of the ventral 

 pharyngeal wall, medial and slightly caudal to the ventral ex- 

 tremity of the sixth gill-pouch (fig. 1). 



Fig. 1 Transverse section through the pharynx of an embryo 20.6 mm. long 

 (H. E. C. 1494) at the level of the suprapericardial body. X 40. The cavities 

 of the heart and blood vessels are in solid black. Ph., pharynx; V, VI, fifth 

 and sixth gill-pouches; P., pericardium; L.s.b., left suprapericardial body. 



