No. I.] 



THE ECHINODERM EGG. 



331 



enter at any point and the first cleavage passes through or near 

 this point. In the absence of a "quadrille" this fact is easily 

 comprehensible, but very difficult to explain if a copulation of 



Fig. 4. Toxoptieustes. A, cleavage-amphiaster in the anaphase ; B, daughter- 

 nucleus, with archoplasm-mass, soon after division; C, " resting-nucleus" of 

 2-celled stage, after fission of the archoplasm ; A cleavage-nucleus of double- 

 fertilized egg, with four asters, at a stage a little later than Fig. 3, C. 



centrosomes really occurs. It will hardly be denied that this 

 double confirmation by circumstantial evidence of the results 

 of direct observation gives a very strong case against the 

 "quadrille" in Toxopncustes, and justifies a skeptical view of 

 Fol's conclusions. 



