202 ANA HROIilC MI:T. I HOLISM 



Perlzweig' and Barron (1928) found, in unfertilized 

 eggs of Arhacia punctulata, 3.14 mg. of lactic acid per 

 gram of egg protein if the eggs were kept in normal sea 

 water, but 5.68 mg. if the medium contained 0.02 per 

 cent potassium cyanide, i.e., if aerobic processes were 

 largely eliminated. Similar experiments, giving identi- 

 cal results, were performed with fertilized Paracentrotus 

 eggs by Eapkine (1931). (Ashbel, 1929 and 1929a, had 

 demonstrated, by a manometric method, that anaerobic 

 glycolysis is much more pronounced in fertilized than in 

 unfertilized sea urchin eggs). Glycolysis may also pre- 

 vail in the anaerobic metabolism of adult echinoderms, 

 but this has not been proven definitely b}^ experiments 

 under anaerobic conditions. Boyland (1928), however, 

 demonstrated that the lactic acid content of fatigued mus- 

 cles of HolotJmria nigra is greater than that of normal 

 muscles. In fatigue, as is well known, products of in- 

 complete oxidations accumulate, due to a shortage of oxy- 

 gen, and one is therefore justified in assuming that the 

 same processes take place under anoxic conditions. 



Lactic acid seems also to be the only end product of 

 anaerobic carbohydrate metabolism in some lamelli- 

 branchs and perhaps in other molluscs. Boyland (1928) 

 performed, with various species of Pecten, Bncc'mum, Ele- 

 done and Sepia experiments similar to those mentioned 

 above with echinoderms. Some lactic acid, though not 

 very much, was formed in all cases. Kobayashi (1929) 

 also found an increase in the lactic acid content of fa- 

 tigued muscles of Ostna circumpicta. 



Experiments with isolated tissues of oysters were car- 

 ried out by Chapheau (1932^, 1932a). He demonstrated 

 first by chemical analysis that lactic acid was actually 

 produced, then he determined manometrically its quan- 

 tity. The gills and the hepato-pancreas had the highest 

 rate of lactic acid formation, the muscle the lowest. 

 Three-year-old oysters formed only about half as much 



