THE OILS OF THE SEA URCHIN AND STAR FISH EGG. 



IRVINE H. PAGE.i 



The fatty fraction of the Echinoderm ova is particularly 

 important because there is evidence that this fraction furnishes 

 much of the energy requirement for the development of the egg. 

 The sterol content of the eggs has been determined and a new 

 sterol found in the star fish egg (Asterias forbesii] by Page (i). 

 The sea urchin (Arbacia punctulatd) egg was shown to contain a 

 rather large quantity of true cholesterol. It seemed desirable 

 now to examine the oil contained in these eggs, the results of 

 which analysis are presented in this paper. 



OIL CONTENT. 



The eggs were removed from the ovaries, strained, and strongly 

 centrifuged to remove as much sea water as was possible. They 

 were then placed in a flask and extracted first with an alcohol- 

 ether mixture followed by repeated ether extractions for eight 

 days at 40 degrees C. in a thermostat. Some of the excess ether 

 was allowed to evaporate at room temperature and then acetone 

 added in large excess in order to precipitate the acetone insoluble 

 phosphatide fractions. After standing over night the mixture 

 was filtered and the solvent from the filtrate allowed to evaporate 

 at room temperature. The residue from this evaporation was 

 placed in a CaCl 2 desiccator and the desiccator kept in the 

 thermostat at 40 degrees C. for 4 days. The residual oily 

 material was then subjected to the identification procedure 

 detailed below. The phosphatide fraction was dried at 100 

 degrees C. and weighed. 



PROTOCOLS. 



Arbacia Oil. The oil had a brownish red color and smelled 

 strongly of lower fatty acids. The material had a heavy con- 

 sistency and tended to lump together. It was freely miscible 



1 Contribution from the Research Division of Eli Lilly and Company, Marine 

 Biological Laboratory, Woods Hole, Mass. 



164 



