OF EXPERIMENTAL WORK I 63 



Carbon Monoxide. — M. M. Brooks, 1933; Clowes and Krahl, 1940; Krahl and 

 Clowes, 1940; Krahl, p. 194, 1950). For P. lividus see Runnstrom (1930); for Den- 

 draster excentricus see Pease (1942 c). 



Carcinogenic Hydrocarbons. — Choleic acid compounds. Delayed cleavage (Luck^, 

 Parpart, and Ricca, 1941). Accelerated cleavage (Keltch, Krahl, and Clowes, 1937). 



Chloral Hydrate. — Fisher and Henry, 1944). See under Anaesthetics above and 

 Tables 13 and 15. 



Chloretone. — Cleavage checked by 0.08% (Heilbrunn, 1920 a, p. 233). 



Clavacin. — Antibiotic (Cornman, 1949). 



Colchicine. — About io~* M. Mitosis stopped in late prophase or metaphase (Nebel, 

 1937; Nebel and Ruttle, 1938; Beams and Evans, 1940; Wilbur, 1940; Cornman 

 and Cornman, 195 1). For Ps. microtuberculatus see Zeuthen (1951, p. 59). For a 

 historical review, see Eigsti, Dustin and Gay- Winn (1949). 



Cold. — Progressive delay as temperature is lowered from about 31° C. (Loeb and 

 Wasteneys, 191 1 a; Loeb, 1913a, p. 32; Loeb and Chamberlain 191 5; Hoadley and 

 Brill, 1937; Villee and Villee, 1952; Tables 3, 4, and 19). For Ps. microtuberculatus, 

 Sphaer echinus granularis see Peter (1905) ; for P. lividus see Ephrussi (1933) ; for 5. pur- 

 puratus, Lytechinus anamesus and Dendraster excentricus see Tyler (1936 a, b). 



Copper Chloride. — 1/62,500 CuClj in sea water prevents cleavage; 1/500,000 pre- 

 vents fertilization (F. R. Lillie, 1921b). See also Hoadley (1923); Glaser (1923); 

 Waterman (1937). Runnstrom (1939) removes poisonous effect of copper by shaking 

 the eggs. Acceleration in very dilute solutions, io~^^ M (Finkel, Allee, and Garner, 

 1942; Allee, Finkel, et al., 1942). 



Corticotropin. — ACTH. (Menkin, 1952, 1953, Proc. Exp. Biol. Med. 82 : 189-194). 



Cortisone. — And desoxycorticosterone (Cornman, 1950 c; Menkin, 1952). 



Cresols. — See Phenols. 



o-Cresol Indophenol. — (Clowes and Krahl, 1936a; Krahl, 1950, Table VHI). 



Crowding. — Cleavage delayed if eggs are very dense; accelerated if moderately 

 dense (Allee and Evans, 1937a). 



Cyanides. — Cleavage arrested by about io~* M to lO"* M (Krahl, 1950, p. 192 

 and his Table V). Data of different observers are given under Cyanides. The re- 

 quired concentration depends on the pH (Krahl). Acceleration of cleavage in very 

 weak concentrations, about io~® M (Lyon, 1902). Reversal of cleavage inhibition 

 by adenosine triphosphate (ATP). (Barnett, 1953). 



Desoxycorticosterone. — (Cornman, 1950 c; Menkin, 1952). 



Deuterium oxide. — See Heavy Water. 



Dimethyl-p-phenylene diamin£.— (Clowes and Krahl, 1936 a; Krahl, 1950, Table 

 Vni). For P. lividus see Runnstrom (1930, 1932). 



Dinitrophenols. — And dinitrocresols. See Phenols. 



Dinoflagellate Contaminated Sea Water. — See "Red tide." 



Dithiocarbamates. — (Krahl, 1950, Table VHI). 



Echinochrome. — (Woodward, 1918). But Allee, Finkel, et al. (1942) find no effect. 



Egg or Embryo Extracts or "Water". — (Glaser, 1913, 1914b; F. R. Lillie, 1921b; 

 Springer, 1922; Peebles, 1929; Allee and Evans, 1937b, c; R. D. Allen, 1951). Some 

 extracts accelerate (Allee, Finkel, et al., 1942). 



Eserine. — Inhibition of cleavage (Villee and Villee, 1952). Stated to accellerate 

 in low concentrations (Balzer and Villee, 195 1). 



Gliotoxin. — Antibiotic (Cornman, 1949). 



Glutamic Acid. — (King, 1912). 



Glycerine. — (R. S. Lillie, 1903). 



Glycocol. — Cleavage normal, later development slow (King, 191 2). 



Halophenols and Halocresols. — See Phenols. 



Heat. — Highest temperature permitting any cleavage lies between 30.4° C. and 

 32.7° C; optimum 24° C. or 25° C. (Hoadley and Brill, 1937). See Acceleration. 



