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FREDERICK TILNEY AND LUTHER F. WARREN 



end-vesicle which is much folded and highly vascular, being 

 mushroom in shape. This sac has much to suggest glandular 

 activity. No tractus pinealis could be discovered in the stalk. 

 The end-vesicle lies beneath the roof in the frontal region and 

 there is in this particular area an actual frontal or parietal fora- 

 men. The parapineal organ is tubular in form and lies in front 



Fig. 58 Cross section of pineal organ and dorsal sac in Argyropelecus hemigym- 

 nus, according to Handrick, 1901. 

 Ds., dorsal sac; Po., pineal organ. 



of the pineal organ. It is shorter than the pineal organ and does 

 not reach the parietal foramen. It has a long stalk. Stud- 

 nicka 386 thinks Handrick' s parapineal organ is nothing more than 

 a peculiar formation of the dorsal sac. 



20. Opsanus. Terry ('II). 392 The pineal organ in this species 

 presents an oval end-vesicle with a long slender stalk, both of 



