198 WILLIAM C. YOUNG AND HAROLD H. PLOUGH. 



temperature causes loss of motility of the sperm, with progressive 

 aggregation and degeneration. Few or no sperms are found in 

 the lower end of the testis and the vas deferens. 



5. Although such males copulate with females at high tem- 

 perature, no sperms pass into the ventral receptacles of the 

 females. 



LITERATURE CITED. 



1. Northrop, J. H. 



'i9-'2o J. Gen. Physiol., II, 313. 



2. Plough, H. H., and Strauss, M. B. 



'23-'24 J. Gen. Physiol., VI, 167. 



3. Strauss, M. B. 



'25 Am. Nat., LIX., July-August. 



4. Moore, C. R. 



'24-'25 Am. J. of Anat., 34, 269, 337. 



5. Bluhm, A. 



'24 Arch, fur Rass. u. Gesellschafts-Biol., 16, i. 



6. Mavor, J. W., and D. M. DeForest. 



'25 Proc. Exp. Biol. Med., XXII, 19. 



