522 E. N. PAVLOVSKY AND E. J. ZARIN 



The experiments prove that in spring, besides the stomach, 

 catalase is produced only by the large intestine (experiments 

 A, C, D). The remaining two portions of the intestine (crop 

 and small intestine) do not produce catalase either separately 

 or combined with others (B) ; in summer during normal 

 nutrition of the bees this ferment is produced only by the 

 stomach. 



In order to study the influence of the time during which the 

 extract from the intestine is infused upon the activity of the 

 catalase, the following experiments were conducted. In one 

 portion the separate parts of the intestine were carefully rubbed 

 together with desiccated sea-sand in the presence of several 

 drops of glycerine ; the emulsion produced was diluted with 

 a mixture of equal parts of glycerine and water with the addi- 

 tion of 10 drops of totuol ; in another portion quite identical 

 extracts, with the only difference that pieces of intestine were 

 directly placed in a mixture of glycerine and water without 

 being rubbed. 



The catalase was determined for periods shown in Table III, 

 in which the results obtained are shown. 



An examination of the data represented in Table III reveals 

 the following. Catalase was as usual produced only by the 

 stomach of the bee. The quantity of ferment proved to differ 

 sharply in extracts prepared from rubbed and intact stomachs. 

 In the first extract (no. 17) after half an hour standing there 

 proved to be nearly three times as much ferment as in the 

 second (no. 17 a). 



The activity of the ferment in the succeeding days differed 

 in both extracts. In the extract from rubbed stomachs the 

 activity of catalase invariably decreased right to its complete 

 disappearance, which was established by us on the thirtieth 

 day. In the parallel experiment with intact stomachs the 



