Collodion Sacs for Bacterial Cultivation. 121 



the other seven animals were killed sixty-four days after being 

 placed on the diet (age about one hundred and fourteen days). 

 The animals in cage "U-V" (rayed animals) were exposed to the 

 radiations at a distance of three feet for varying periods of time 

 daily for sixty-four days and were then killed. 



The rayed animals as contrasted with the control animals 

 showed marked physical vigor as evidenced by growth, activity, 

 good appetite, thick smooth coats and reproductive power. 



Autopsies showed the rayed animals to be larger than the con- 

 trols and to have great increase over the controls in the amount 

 of fat deposition and muscular development. The rayed animals 

 showed no evidence of rickets. The control animals showed 

 enlargement of the epiphyses of the long bones, deformities of the 

 thorax, enlargement of the costo-chondral junction and fractures 

 of the ribs. Histological examination showed the long bones of 

 the rayed animals to be normal and those of the control animals 

 to have typical rickets. 



The effects of the radiations of the mercury vapor quartz lamp 

 on the growth and calcification of the skeleton of the rat and on 

 the animal as a whole seem to be similar if not identical with those 

 brought about by direct sunlight and by cod liver oil. 



59 (1806) 



Collodion sacs for aerobic and anaerobic bacterial cultivation. 



By FREDERICK L. GATES. 



[From the Rockefeller Institute for Medical Research, 

 New York City.] 



The collodion sacs demonstrated before this society a year 

 ago, 1 while suitable for intraperitoneal implantation are not so 

 well adapted to microbic cultivation in vitro. We have therefore 

 been making sacs of 5-10 c.c. capacity in test tubes lined with a 

 dried film of gelatin 2 which softens in warm water and permits 

 the easy removal of the collodion membrane. The sac is slipped 

 on to a supporting glass tube, inserted into one limb of a V-shaped 



1 Proc. Soc. Exper. Biol, and Med., 1920, xviii, 92. Jour. Exper. Med., 

 1921, xxxiii, 25. 



2 The 10 per cent, gelatin solution is preserved with 0.3 per cent, tricresol. 



