THE PINEAL BODY 



149 



In form the avian epiphysis is conical or cylindrical, sometimes 

 being flattened by the approximation of the cerebellum and 

 cerebral hemispheres. Its size varies considerably in different 



R Ch 



ct> 



Fig. 73 The pineal region in Callus domesticus, according to Studnicka, 1896. 

 Ds., dorsal sac; Ch., commissura habenularis; R., recessus pinealis ; St., pineal 

 stalk; Ep., pineal body; Cp., commissura posterior. 



species, but the following figures give a general idea of the 

 dimensions. 



In Meleagris gallopavo 5 mm. long by 2.5 mm. thick 



In Callus domesticus 2.5 mm. long by 1.5 mm. thick 



In Strix 6 mm. long 



