426 THE PINEAL ORGAN 



and obtained a retardation of metamorphosis. This result is, however, 

 counterbalanced by the results of experiments published by M'Cord in 

 1 91 7, in which he states that : "In unicellular organisms (paramoecia) 

 pineal extract increases the rate of reproduction to more than double that 

 of the controls " ; and " in larval forms (Ranidce) both growth and 

 differentiation are hastened." 



Berblinger, experimenting on young rats, injected alcoholic and watery 

 extracts of the epiphyses of oxen subcutaneously, and also administered 

 the pineal by way of the alimentary tract. He obtained positive results 

 in most, but in some there was an increase in size. 



Calvet also experimented on immature white rats, using epiphyseal 

 extracts obtained, fresh, from entire horses, geldings, and mares. These 

 were ground aseptically in a mortar and mixed with equal parts of physio- 

 logical serum. The animals received daily injections of this solution for 

 8 days, and were killed two days after the injections had been discon- 

 tinued. The testicles were slightly smaller than those of the controls, 

 but the size of the animals remained practically the same as the controls. 



Negative Results. — M'Cord fed young chickens and guinea-pigs with 

 food containing a mixture of desiccated pineal gland and lactose. The 

 control animals received a similar food containing the same amount of 

 lactose but without the pineal. In both cases there was an acceleration 

 of growth in the experimental animals. At the end of two weeks the 

 guinea-pigs fed with pineal substance showed an increase in weight of 

 100 per cent., as compared with an increase of 77 per cent, in the controls. 

 The author, however, noted that the action was variable (Fig. 283), and 

 that if young animals were fed with epiphyses obtained from aged oxen, 

 there was a diminution in weight. 



Negative results, namely, acceleration of development and increase of 

 weight, have also been obtained by Roux in frog tadpoles, Calvet in 

 tadpoles of Alytes, M'Cord (previously mentioned) in Ranidce, by 

 feeding with desiccated epiphysis, and also by Calvet with daily injections 

 of Epiglandol into immature rats, 1 c.c. of Epiglandol being equal to 

 0-02 grm. of the fresh gland. The injected animals killed three weeks 

 after weighed 34 grm., while the largest of the controls weighed only 

 31 grm. Notwithstanding this somatic increase, the testicles were not 

 hypertrophied and macroscopically appeared even smaller than those 

 of the controls ; moreover, microscopical sections showed no appreciable 

 change in structure. 



In discussing the various results of these experiments depending on 

 the use of desiccated epiphysis or extracts of the epiphysis, Calvet puts 

 forward the suggestion, based on the biochemical researches of Fenger 

 and Roux, that since phosphoric acid, calcium, magnesium, sodium, and 



