Paramecium Polycaryum 



339 



and the micronuclear structure of the "aurelia type," but pos- 

 sessing several (three to eight) micronuclei. In brief, the or- 

 ganism is essentially identical in form and structure with P. 

 calkinsi, but has more than two micronuclei. Thus from the 

 standpoint of micronuclear structure and number this animal 

 holds the same position in the "bursaria group" as P. multimicro- 

 nucleata in the "aurelia group." 



Pedigree cultures from the original animal found have now 

 been under observation and experimentation for nearly four 

 months, and through upward of one hundred and fifty genera- 

 tions. During this time the animals have bred true, exhibiting 

 the characteristic micronuclear number after emerging from the 

 nuclear reorganization involved in endomixis. 



In view of all the above data the animals of this culture are 

 designated a new species, Paramecium polycaryum. 2 



164 (2124) 



The effect of iletin (insulin) on the blood sugar content in 

 adrenalectomized animals. 



By G. N. STEWART and J. M. ROGOFF. 



[From the H. K. disking Laboratory of Experimental Medicine, 

 Western Reserve University.] 



The existence of a close relationship between the adrenals, 

 especially the medulla, and the pancreas in the regulation of the 

 carbohydrate metabolism has been assumed by various writers. 

 It seemed therefore of interest to determine whether the action 

 of insulin on rabbits which had survived total adrenalectomy 

 differed from its action on normal rabbits. No difference was 

 made out. The adrenals were removed in two operations. The 

 second adrenal was excised 3 weeks to 8 months before the in- 

 sulin experiment. Six to eight blood specimens were obtained 



2 Details of the structure and life history of P. polycaryum will appear in 

 the Biological Bulletin. 



