62 SUMMARY OF CURRENT RESEARCHES RELATING TO 



ing has any deleterious effect on the vitality of the stock. But there is 

 some evidence that congenital weakness due to old age conjugation is 

 inherited by the later offspring. J.. A. T. 



Life-history of Sarcocystis tenella. — John W. Scott {Proc. Amer. 

 Soc. Zool. in Anat. Record, 1920, 17, 382). Lambs with ewes have 

 been reared in a screened cage, insect-free except for a few small transient 

 gnats, and with a cement foundation preventing the ingress of mice or 

 other animals that serve as hosts of the parasite. Nevertheless the 

 muscles of the lambs were infected. It is probable tliat the life-history 

 is a direct one, and that infection takes place by means of food recently 

 contaminated with fresh fgeces from an infected sheep or lamb. There 

 may be a hitherto scarcely suspected, probably sexual, stage of Sarcocystis 

 tenella in the intestine of the host. J. A. T. 



