160 CARL RICHARD MOORE. 



exposure to the acid varying with conditions. Eggs over-exposed 

 to the acid agglutinate heavily, but they neither produce mem- 

 branes nor disintegrate exceptionally fast. The individual eggs 

 vary in appearance but little from normal unfertilized eggs but 

 all efforts to fertilize such eggs have resulted in complete failure. 



Why has the fertilization capacity disappeared? If sperm 

 could enter these eggs would the reaction appear? 



(a) Cytological Observations. From the experiments, lots of 

 eggs were preserved that had suffered the shortest possible 

 exposure that would prohibit cleavage. 



Examination of sections revealed the fact that practically 

 all the eggs contain sperm nuclei, many sections showing 8 or 10 

 in one plane of section. They are located at all planes of the 

 egg from periphery to center. These sperm however give no 

 evidence whatever of being either effective or effected. Similar 

 to the conditions encountered in the optimum butyric acid 

 exposure the sperm do not produce asters. They appear entirely 

 as foreign bodies suspended in the cytoplasm. Their contour 

 has suffered no noticeable change but they retain their usually 

 oblong pointed appearance. They do not react with the egg. 

 Something is absent with which or to which they normally react. 



We can not conclude that the eggs are dead and thus veil our 

 ignorance, for how then could we account for the presence of 

 spermatozoa? It is inconceivable that the spermatozoon could 

 acquire enough momentum to penetrate the surface of the egg 

 and to carry itself on through a mass of protoplasm very roughly 

 estimated as 15 to 20 times its own diameter. It cannot bore 

 its way through, for were it possessed of a perforatorium 

 (which it is not) the tail would be completely buried long before 

 it reached the center of the protoplasmic mass even if the tail 

 remained in contact with the sperm head. The very fact that 

 spermatozoa have entered the eggs is proof that the eggs are not 

 dead. The normal environment for the activity of the sperm 

 has been changed. Something again is absent that would nor- 

 mally permit the reaction and the consummation of development. 



IV. EFFECTS OF A RISE OF TEMPERATURE ON FERTILIZATION. 



While studying the effects of altered temperatures upon the 



process of development the writer found that by subjecting sea 



