REPRODUCTION 51 



ments was frequent. The offspring of male rabbits 

 treated with lead acetate were smaller and had distinctly 

 lower vitality than the offspring of normal parents under 

 similar conditions. The results from lead-poisoning of 

 male fowls indicated that their offspring is of distinctly 

 lower vitality than of offspring from normally healthy 

 fowls. 



The importance of these investigations to the practi- 

 cal breeder lies not in the fact that alcohol and other 

 poisons may modify the male germ-cell and subsequently 

 the offspring, but that the sperm-cell is capable of such 

 reactions to environmental conditions that the progeny 

 are profoundly changed or their development entirely 

 prevented. If the offspring may be so modified through 

 the sperm-cell by alcohol and lead acetate, then it is in all 

 probability susceptible to other influences. It is a well- 

 known fact that many conditions in ordinary breeding 

 practice do modify the birth rate and the characters of 

 the offspring. Certain feeds are known to have a more 

 or less definite relation to the breeding powers. Investi- 

 gations under proper control planned to test the influence 

 of special feeds on the sperm-cell are lacking. At vari- 

 ous times breeders have reported that alfalfa, clover, sugar 

 and other materials when fed to breeding females have 

 resulted in difficult conception or in weak offspring. 

 Whether these feeding stuffs have an injurious effect on 

 the male germ-cell is not known and cannot easily be 

 determined in ordinary farm practice. 



