76 M. F. GUYER AND E. A. SMITH 



3. EFFECTS OF LENS CYTOLYSINS ON FETAL MICE 



The experiments on mice were performed by the senior author 

 at the Scripps Institution for Biological Research at La Jolla, 

 California. His thanks are due this institution for many courte- 

 sies. He is particularly indebted to Dr. F. B. Sumner and 

 Mr. H. H. Collins for their generosity in adding to his stock of 

 mice, for identification of species, and for information about 

 breeding and rearing Peromyscus. 



Chickens were used as the source of antibodies and lenses of 

 Peromyscus maniculatus gambeli were employed as antigens. 

 The fowls, averaging three and eight-tenths pounds in weight, 

 were gradually sensitized, as specified in table 3, by repeatedly 

 injecting emulsified lens intraperitoneally. To prepare this 

 emulsion a number of lenses were ground up in a mortar in a 

 little normal salt solution. When thoroughly pulped the mix- 

 ture was thinned with more of the salt solution so that it could 

 be readily injected by means of a hypodermic syringe. The pro- 

 portions of lens and of saline solution in the various injections 

 are specified in table 3. The individual fowls injected, ten in 

 number, are arbitrarily designated by the letters A, B, C, etc., 

 to J. 



The purpose of the present experiments was to build up a lens 

 cytolysin which when injected into pregnant mice (Peromyscus 

 maniculatus gambeli) would have a solvent effect on the lenses 

 of the young in utero. Judging from the results of earlier ex- 

 periments on the rabbit, no effect on the lenses of the mothers 

 was anticipated. 



Precipitin tests 



Inasmuch as there is no visible way to tell when serum is 

 adequately sensitized for use as a cytolysin beyond trying it out 

 directly, and since both time and the supply of pregnant females 

 were limited, a series of lens precipitin tests were made with 

 various of the fowls after the fifth and sixth injections, respec- 

 tively in order to be sure that they were responding to the lens 

 proteins. While there is possibly no necessary connection be- 



