378 A. J. GOLDFARB. 



other samples of the same female were examined, and the results 

 reduced to percentages as recorded in Table I. 



I have shown (Goldfarb, '17) that the freshly liberated eggs of 

 different females vary considerably in the per cent, possessing 

 the jelly layer. In Hipponoe the per cents vary from 100 to 63 

 per cent., in Arbacia from 100 to 59 per cent. These differences, 

 I suggested, indicated corresponding differences in physiologic 

 condition of the eggs at the time of liberation. 



Whatever the condition of the eggs at the time of liberation, with 

 increasing age there was a continuous decrease in the number of eggs 

 with the jelly layer present. 



The data may best be considered in two groups, according to 

 the physiologic condition of the eggs at the time of the first 

 observation. 



In the first group are those females whose eggs were in good 

 physiologic condition. This was indicated by the high per cent. 

 (i. e., above 95 per cent, with jelly layers) at the first observation, 

 as well as by other tests. In this group are placed females 2, 3, 4, 

 5, 6, 8 and 12, and the corresponding percents of jelly layers was 

 97, 100, 100, 100, 96, 95 and 99 respectively. 



In the second group are placed those females whose eggs 

 were in poor physiologic condition. In this group are included 

 females 7, 9, 10 and n, whose corresponding jelly counts were, 

 86, 90, 63 and 80 per cent., respectively. 



In both groups the surrounding jelly layer progressively dis- 

 appeared with age, as seen in Table I. But the rate of loss was 

 different. An example of the first group is female 8. When o 

 hours old, 95 per cent, possessed the jelly layer, when 18 hours 

 old 95 per cent., and when 24 hours old only 72 per cent, retained 

 the layer. Female n is an example of the second group in 

 which the loss was decidedly greater. The eggs when 3 hours 

 old showed 80 per cent, with jelly layers, when 9 hours old but 10 

 per cent., when 27 hours old only I per cent., and when 33 hours 

 old none of the eggs possessed the jelly envelope. 



The two groups differ then, not only in original per cent, with 

 jelly layers, but also in the rate of loss of this layer. In the first, 

 containing physiologically good eggs, the loss of the jelly layer per 

 hour, for the indicated intervals for the different females, was 0.7, o.o, 



