150 ALPHABETICAL COMPILATION 



Historical. — Observed by Valentin in 1841 (published in one of the Monographies 

 d' £chinodermes of L. Agassiz) in Echinus lividus ( Paracentrotus lividus) ; by Williams 

 (1852) in E. spaera (E. esculentus) ; by Geddes (1880) and Gamgee (1880) in Arbacia 

 lixula; by MacMunn (1883, 1885) in P. lividus; by Cu^not (1891a, b) in many 

 species; et al. In Arbacia punctulata, McClendon (1912a) and McClendon and Mit- 

 chell (19 1 2) et al., refer to them as "elaeocytes." This term really means oil or fat 

 cells, and was originally applied to yellowish lymphocytes, not amoeboid, containing 

 fat, in the coelomic fluid of certain oligochaetes (Rosa, 1896). 



Occurrence. — In Perivisceral Fluid, q.v., (Mathews, 1900; McClendon, 1910b, 

 1912a, McClendon and Mitchell, 191 2; Kindred, 1921, 1926; H.V.Wilson, 1924; 

 Donnellon, 1938; et al.). Throughout body, especially around testes and ovaries 

 (E. B. H. unpub.). 



Color. — Red and white amoebocytes occur in about equal numbers. The red ones 

 owe their color to Echinochrome, present in Chromatophores, q.v. 



Amount of Echinochrome. — In amoebocytes: 3.78 gm. per 100 cc. of packed volume 

 of body cells; the eggs contain on the average 0.58 gm. of pigment per 100 cc. of 

 eggs packed by centrifuging (Ball and Cooper, 1949). 



Pigment Released. — By water, tissue extracts, salts especially potassium, hypertonic 

 solutions, fat solvents, mechanical and electrical stimulation, ultraviolet light, cold, 

 heat; but it is not released if the body fluid is oxalated or citrated, under most of 

 these conditions (Donnellon, 1 938) . Release by electric current was earlier observed by 

 McClendon (1910b). 



Colorless Amoebocvtes. — Of body fluid swell and dissolve if NaCl, KCl or MgClj are 

 added to the sea water (Mathews, 1900). 



Shape. — Cylindrical or spherical. Decidedly amoeboid. Become spherical on addi- 

 tion of water and with ultraviolet light and x-rays (E. B. H. unpub.), and with 

 hydrostatic pressure (Marsland, 1938). 



Size. — Cylinders average 30 ft long by 7.3 ju diameter; volume 1256 /a^. Spheres 

 average 13.3 /i diameter; volume 1232 ju^ (E. B. H. unpub.). 



Stain. — Colorless amoebocytes are basophilic, red ones acidophilic (Kindred, 

 1926). 



Function. — Not certain. Red ones may be respiratory (Geddes, 1880; Gamgee, 

 1880; MacMunn, 1885; in other species). See under Echinochrome. Cause clotting 

 of perivisceral fluid (Heilbrunn, 1928, p. 228; Donnellon, 1938). 



Fertilization. — Inhibited by amoebocytes (Pequegnat, 1948), probably due to 

 echinochrome (Couillard, 1952). 



Other Species (additional) 



Davidson, 1953. Echinarachnius parma. 



Kindred, 1924. Sirongylocentrotus drobachiensis, S. franciscanus, Echinarachnius excentricus. 



AMOEBOID EGGS 



Amoeboid Eggs. — These are caused by 

 Standing overnight (E. B. H. unpub.). 

 Urea (R. S. Lillie, 1903; Moser, 1940; Kitching and Moser, 1940; A. R. Moore, 



1929, in S. purpuratus) . 

 Sucrose (Kitching and Moser, 1940). 



Ethyl urethane, 0.4 M for i hr. (E. B. H. per E. N. Harvey, 1933). 

 KCl (Churney, 1940). 

 MgClj (Loeb, 1900 a; Churney, 1940). 

 Electric current, at anode (McClendon, 1910b). 

 Photodynamic action, light -\- rose bengal or eosin (Alsup, 1941). 



