OF EXPERIMENTAL WORK 1 89 



Shape. — Irregular with long filamentous processes or pseudopods (Kindred, 192 1, 

 1926; H. V. Wilson, 1924; Liebman, 1950). 



Phagocytosis and Clotting. — (Kindred, 1921, 1926; H. V. Wilson, 1924; Donnellon, 

 1938; Liebman, 1950). Trephocyte material taken up by oocytes (Liebman, 1950). 



Other Species 

 Kindred, 1924. S. drobachiensis. 



LIPIDS 



See also Oil 



In eggs. — Cholesterol present in Arbacia egg, not in Asterias (Mathews, 191 3; Page, 



1923^ 1927a). 



Cephalin, more; lecithin, less in Arbacia than in Asterias (Page, 1927a). No change 

 in lecithin (?) content between 2-cell stage and blastula (Shackell, 191 1); this was 

 criticised by Robertson and Wasteneys (1913) who found decrease in lecithin in 

 Strongylocentrotus purpuratus. 



Amount. A. In alcohol-ether extract, 8.3 gm. of oil from 183 million eggs; 1.539 

 gm. of acetone-insoluble material with high percentage of cephalin. Iodine number 

 of oil 146-148, saponification value approximately 606 (Page, 1927a). 



B. Total fat (all material soluble in petroleum ether) in a million unfertilized eggs 

 is 5.65 mg; sterol 0.43 mg. or 7.5 % of total fat; phospholipid 2.17 mg. or 38 % of 

 total fat. Total fat decreases up to time of hatching (8 hrs.), increases for 10 hrs., 

 then decreases; sterol unchanged and phospholipid uncertain. Loss of total fat in 

 43 hrs. is 3.54 mg. per million eggs (Hayes, 1938). 



C. Total lipid ("lyophylled" eggs), 5.4% of whole egg, 26.9% of solids in egg; 

 77 % of total lipid is probably bound to protein. No change in total or bound lipid 

 in 5 hrs. development (Parpart, 1941). 



Crude oil obtained with fat solvents is reactive with Nadi reagent. 1 2 index 180- 

 190, saponification index around 200. Sterols and phospholipids present, also fatty 

 acids and glycerids (Navez, 1938, 1939; Navez and DuBois, 1940). 



In Centrijuged Eggs. — (Ether extract). Amount. Whole eggs 2.254% total fat; cen- 

 tripetal layer of centrifuged crushed eggs 0.3 %; centrifugal layer 1.946 % (McClen- 

 don, 1909 a). 



In Half-Eggs. — (Obtained by centrifuging) . White half-eggs: free fats and sterols 

 (ether extract) 2.2 mg. per million halves; bound lipids (alcohol-ether extract) 

 9.6 mg. per million halves. 



Red half-eggs: free fats and sterols 6.6 mg. per million halves; bound lipids 12.2 

 mg. per million halves. 75 % of free fats and sterols, 56 % of bound lipids are in red 

 half, or 61.6% of total lipids (Hunter and Parpart, 1946). 



In Nucleoli. — Lipids and phospholipids not present in nucleoli oi Arbacia, as deter- 

 mined by staining (Gates, 1941). 



In Sperm. — Lipoids and lipoproteins present in acrosome, middle piece and tail, 

 on the surface (Popa, 1927). Lipids in alcohol-ether extracts do not contain agglu- 

 tinating substance; this is in protein residue (Frank, 1939). 



Effect on The Eggs: — Of fatty acids. Cause parthenogenesis, especially butyric 

 (Loeb, 1913a, p. 71, etc., et al., see under Parthenogenesis. Decrease viscosity 

 (Howard, 193 1). Of soaps. Different effects by different soaps on cytolysis, pigment 

 discharge, stratification and breaking with centrifugal force and on response to 

 microdissection (Page, Shonle, and Clowes, 1923). 



Other Species (additional) and General References 



Cleland and Rothschild, 1952 a. Echinus esculentus, eggs, analysis. 

 Ephrussi, 1933. Paracentrotus lividus, analysis. 



