4 A. J. GOLDFARB. 



whether fertilized or unfertilized. And when fertilized they 

 agglutinated equally well whether old or fresh sperm were used, 

 subject only to the following qualification, viz., when fresh sperm 

 in high concentration were used, they caused the eggs to revolve 

 rapidly in various directions, thereby preventing adjoining eggs 

 from agglutinating, and separating many of the eggs already 

 agglutinated. This was observed in Toxopneustes, experiment 

 i, 2, 3, 4; in Arbacia, experiment 16, 17; in Hipponoe, experiment 

 14, etc. 



Clusters of 2 to 40 and more eggs were agglutinated to one 

 another. Large clusters died in early cleavage. Clusters of 3 

 and 4 eggs often reached the blastula stage, and sometimes 

 the gastrula stage, and then died. Clusters of 2 frequently 

 reached the larva stage. The various types of gastrula and 

 larvae resulting from such agglutinated pairs of eggs and the 

 processes involved, I have described in a previous publication 

 (Goldfarb, '13, '15). 



Agglutination occurred in every experiment in which the eggs 

 had aged sufficiently, i. e., in which physiologic deterioration 

 had proceeded to a sufficient degree, as determined by the various 

 tests enumerated in Study I. and II. Such deterioration gave 

 rise without any other treatment, to exactly the conditions that 

 were found to be most successful in the experimental agglutina- 

 tion of eggs, namely, loss of jelly layer, loss of membrane and a 

 viscous condition of the naked protoplasm of the egg. 



The rate of physiologic deterioration and hence the rate of 

 agglutination depended upon the condition of the eggs at libera- 

 tion, the species of egg used, the temperature of the sea water, 

 and age. 



FUSION OF EGGS. 



Some of the agglutinated eggs fused more or less completely 

 together in all cultures of aging eggs. Only a small per cent, 

 however fused, partly because clusters of more than 4 eggs died 

 in early cleavage, while clusters of 3 or 4 eggs rarely survived 

 beyond the blastula stage; and partly because clusters of 2 or 3 

 eggs often separated as a result of the uncoordinated ciliary activ- 

 ity of the different component blastula, gastrula or larvae. 

 Therefore only some of the closely agglutinated clusters of 2 or 3 



