PINEAL 141 



selves with the organ. Professor Biedl claims that 

 in adults "the gland is a negligible factor/' He ar- 

 rives at this conclusion from extirpation experi- 

 ments. He has not, however, settled the question 

 of extirpation in young animals. 



Foa, an Italian, has removed the pineal from 

 roosters, with the result that the testes hypertro- 

 phied. Horrax, of Chicago, has practised pineal- 

 ectomy on guinea pigs; he states that the develop- 

 ment of the testes becomes accelerated. The feed- 

 ing of the desiccated pineal body to rats has had 

 no influence on their growth (Finney, Baltimore). 

 Another and more important experiment where 27 

 mentally deficient children at the Vineland farm 

 were fed with a pineal extract, led to no noticeable 

 effect. 



We do know what pathological growths of the 

 pineal gland in children will give rise to. "In the 

 70 cases on record of tumor of the pineal gland, 

 most were in adults, but ten were in boys below 

 the age of puberty; and these all presented pre- 

 cocious and pronounced development of the pri- 

 mary and secondary sexual characteristics, and 

 some a certain degree of mental precocity." (Zan- 

 dren) ; which points to the presence of a hormone 

 that regulates, in some way, the sex life. 



Dr. Frederick Tilney, in his book 1 gives us an 



1 Frederick Tilney and H. A. Riley: The Form and Functions 

 of the Central Nervous System (P. B. Hoeber, New York, 1921). 



