FERTILIZATION REACTION IN ECHINARACHNIUS PARMA. 



mixed. 10:20 A.M., shed eggs from one very fine female exposed 

 to butyric mixture, samples being removed at intervals to dishes 

 of 250 c.c. of normal sea-water. Table I. gives the data. 



TABLE I. 



Eggs of nos. 7-15 showed a tendency to go bad; this increased 

 with the length of exposure, for no. 15 eggs were very bad. 



The results are essentially the same in the experiments of 

 July ii and July 26 as shown in Table II. 



TABLE II. 



1 No exposure for this length of time. 



During August 4, seven lots of eggs from different females 

 were exposed to 2 c.c. n/io butyric acid plus 50 c.c. sea- water for 

 20, 25, 30, 35, 40, 60, 90 and 120 seconds. The 35-second ex- 

 posure in each case gave 91, 90, 98, 93, 99, 97 and 97 per cent, 

 full membranes. Observations of August 6 were about the same. 



