THE INFLUENCE OF CHEMICAL FACTORS 83 



considerable quantities of carbon dioxide. When oxygen is offered to 

 them they are unable to utilize it. The processes taking place in this 

 case were studied by E. Weinland [1901] who found that carbohydrates 

 were the substances chiefly and perhaps exclusively catabolized by 

 Ascaris (J of the dry substance of which is glycogen), the process lead- 

 ing to the production of carbon dioxide and fatty acids, valerianic and 

 caproic. Weinland believes that the process takes place according to 

 the formula : 



4 C (5 H 12 6 = 9C0 2 + 3C 5 H 10 2 + QH 2 



but the hydrogen stipulated has never been observed. 



Lesser [1909-10] has found that analogous processes take place in 

 the earth-worm (Lumbricus) when that animal is deprived of oxygen. 

 Carbon dioxide and fatty acids are produced. When air is administered 

 to earth-worms after an anoxybiotic period an abnormally high oxygen 

 intake is observed with a very low respiratory quotient [1910, 3]. 

 The products of the incomplete breakdown are rapidly oxidized. 



Experiments on anoxybiosis have been made further by Putter 

 on infusoria [1905] and on the leech (Hirudd) [1906-7], but a detailed 

 account seems unnecessary as the methods employed are unreliable 

 and the conclusions arrived at unwarranted, as shown by Lesser. 



On the tissues of chrysalides of flies (Calliphora)^ which were 

 ground to a paste, Weinland [1906] has observed that a catabolism of 

 fat could take place in the absence of oxygen, resulting in the forma- 

 tion of carbon dioxide and free hydrogen. 



Putter [1905] has expressed the opinion that the anoxybiotic 

 metabolism is to be considered as the more general or "primitive" 

 scheme of animal metabolism and the oxidative process as the 

 secondary. This singular proposition probably contains an element 

 of truth, in so far as the initial stage in the breakdown of the foodstuffs 

 is probably not oxidative. Certain animals (endoparasitic worms) are 

 capable only of performing this stage. They are able to excrete the 

 products which are not harmful to them in the concentrations reached. 

 They are absolutely anserobic. Others (like earth-worms) are able to 

 endure want of oxygen for a considerable time. The products of 

 anoxybiosis are not very harmful to them, though their vitality is 

 generally impaired when they remain without oxygen for a long time. 

 In a number of cases the catabolic reactions are probably inhibited by 

 the accumulation of their products and the harmful effects thereby 

 counteracted. 



6* 



