156 CARL RICHARD MOORE. 



at this time is the question of the possibilities of an influence 

 exerted by the sperm, provided it could enter the egg by any 

 means whatever after activation by butyric acid. We should, 

 from hypothesis, expect the reaction to be entirely absent and 

 this I shall prove is the fact. In these preserved series the 

 experiments were conducted in the same manner as that given 

 on page 152. After membranes had been produced as a result 

 of butyric acid and destroyed by shaking, the eggs were trans- 

 ferred to fresh sea water and inseminated very heavily with 

 fresh sperm. Eggs were preserved a't definite periods by killing 

 in Boveri's picro-acetic acid, Bouin's mixture, and Meves' fluid. 

 Sections were cut in paraffin at 4 n and stained with a fresh 

 solution of iron-hsematoxylin. The better results were obtained 

 by staining, following Boveri's picro-acetic acid, in a 0.5 per cent, 

 aqueous solution of haematoxylin first dissolved in a small amount 

 of absolute alcohol and diluted properly with distilled water, 

 using the stain immediately. This gives a clear gray cytoplasm, 

 against which the intensely black sperm heads stand in marked 

 contrast. 



Eggs preserved fifteen minutes after insemination reveal the 

 fact that sperm have entered in large numbers; also that entrance 

 of one sperm does not prohibit the entrance of others. A sec- 

 tion of an egg 4 //. thick may show any number of sperm heads 

 from one to twenty or sometimes more. These spermatozoa 

 are scattered all through the cytoplasm and are not located 

 near one side where accidental injury to the egg might have made 

 entrance possible; they are found at any level of the egg. The 

 majority are located near the periphery of the egg but many are 

 found at the center, close to the egg nucleus and even in loose 

 contact with it. The periphery of many eggs is literally packed 

 with the sperm heads. There seems no definite orientation; 

 sperm side by side or in groups may be turned in opposite direc- 

 tions or yet may lie at right angles or in practically any direction 

 to each other. Evidence of active behavior of such sperm is 

 entirely negative. No asters arise around the sperm heads and 

 neither do they exhibit the tendency to become enlarged and 

 vacuolated as in normal fertilization, especially as the male and 

 female pronuclei approach each other. The only discernible 



