294 



E. E. JUST. 



This observation is cited to show that the stale egg previously 

 treated with butyric acid is capable of developing into larvae. 

 No. i gave good larvae ; Nos. 2 and 3 gave normal larvae ; Nos. 4 

 and 5 were poor, large number of exogastrulse. 



July i. Six determinations on different lots of eggs showed 

 that eggs having 120 seconds exposure lost completely their fer- 

 tilization capacity in 43, 61, 54, 73, 78, and 51 minutes respec- 

 tively. Not a single egg had a membrane, but all had the jelly- 

 like cortex. In each case, the 35 second exposure showed over 

 90 per cent, of eggs intact; the under-exposed eggs were all in- 

 tact. The controls of the six lots showed 16, 19, 7, 14, 9, 3 per 

 cent, cytolysis respectively. 



C. Discussion. 



The foregoing data constitute the evidence for the conclusion 

 that short exposure to 2 c.c. of n/io butyric acid plus 50 c.c. of 

 sea-water prolongs the capacity of the egg to respond more or 

 less normally to insemination. Compared with the normal egg 

 in normal sea-water, the egg which treated with butyric acid fails 

 to form a membrane not only is endowed with certain protection 

 against the cytolytic action of sea-water but also is restrained 

 from a too rapid loss of fertilizing power. This effect as in the 

 case of cytolysis may be produced with one c.c. of w/io butyric 

 acid plus 50 c.c. of sea-water. Indeed, the consequence of the 

 treatment with butyric acid may be an actual improvement of the 

 normal egg as shown by the size, vigor, and longevity of the 

 larva. Thus, eggs treated for ten seconds with the higher con- 

 centration of acid or for twenty seconds with the lower after 

 twenty-four hours in sea-water show one hundred per cent, intact 

 without any sign of cytolysis, whereas control eggs from the 

 same female may show from fifteen to one hundred per cent, of 

 cytolysis observations frequently made during three seasons. 

 Such eggs on insemination yield close to one hundred per cent. 



