84 FERTILIZATION 



(or laying?): Na, -10%; Ca, -8%; CI, -8%; inorganic P, 

 — 16% (conversion to organic P ?). S. salar (Hayes et al., 1946). 



Manery & Irving (1935) found no change in CI when the eggs of 

 Salnto gairdneri Richardson were fertilized. 



(6) Increase in rate of disappearance of pyruvate, added to sea 

 water, after f. ; u., 64)/, f., 448y/hour/g. dry weight. A. piinctulata 

 (Goldinger & Barron, 1946). 



This experiment does not, in fact, tell one anything about the differ- 

 ences between u. and f. eggs in regard to pyruvate metabolism. The 

 authors do not refer to the changes in permeability which are known to 

 occur when sea-urchin eggs are fertilized. Nor did they examine the 

 possibility of different effects on f. and u. eggs of lithium, which was 

 added to the sea water as lithium pyruvate. This paper contains 

 several interesting but speculative observations about fertilization, 

 some of which are now known to be wrong. The earlier negative 

 results on pyruvate metabolism of Runnstrom (1933) and Orstrom 

 & Lindberg (1940) are said to be due to inadequate techniques. 



(7) No change in diphosphothiamine at f. A. pimctulata 

 (Krahl et al., 1942; Goldinger & Barron, 1946). 



The first authors- found 8-5 y/g. dry weight and the second 16-2 yjg. 

 dry weight. Diphosphothiamine is concerned in pyruvate metabolism, 

 as it acts as a coenzyme in the reaction: 



carboxylase 



CHo-CO-COOH -> CH3CHO + CO, 



diphosphothiamine " 



(7-1) Fall in free thiamine and phosphothiamine synthesis after 

 f. O. latipes (Hishida & Nakano, 1954). 



(8) DPN, u., 385 y/g. wet eggs; f. (30 min.), 345; f. (600 min.), 

 242. S. franciscanus, A. piinctulata (Jandorf & Krahl, 1942). 



(9) Decrease in ribonuclease activity after f. A. piinctulata 

 (Bernstein, 1949*). 



(9-1) DNA of f. eggs not formed from RNA of u. eggs. A. 

 pimctulata (Schmidt et al., 1948; Villee et al., 1949). 



(9.2) DNA of f. eggs formed from RNA of 11. eggs. P. lividus 

 (Brachet, 1933). 



It is now generally agreed (Abram?, 1951) that (9.2) is wrong and 

 (9.1) is right. RNA fragments may, however, be utilized in DNA 

 synthesis. 



