NEMATODES 141 



especially those who have been sensitized by previous poisoninj^, some 

 persons being entirely insusceptible. 



An extensive investigation of ascaris from both the chemical and 

 toxicological standpoint has been made by Flury," which indicates 

 the source and nature of these toxic substances. Because of the 

 practically anaerobic conditions under which the worms live, Flury 

 believes, tlie products of their metabolism are characterized by being 

 incompletely oxidized, and resemble the products of anaerobic bac- 

 teria. Most important of these are volatile aldehydes and fatty acids, 

 especially valerianic and butyric acids, in less quantities formic, 

 acrylic and propionic acids. The toxicologic action of these volatile 

 substances is of such a character as fully to explain the severe irrita- 

 tion of skin and mucous membranes observed in persons handling 

 these parasites; aldehydes are notoriously^ inclined to produce con- 

 ditions of hypersensitiveness, e. g., formaldehyde. It is quite possi- 

 ble that the severe constitutional symptoms observed occasionall}^ in 

 persons infected with ascaris, are produced by these substances or 

 by poisonous substances set free through disintegration of worms 

 which have died and remained in the bowel. A capillary poison re- 

 sembling sepsin, poisonous bases acting like atropine and coniine, 

 and hemolytic unsaturated fatty acids were also found, among other 

 less toxic substances produced by ascaris, and the sum of their ac- 

 tion is certainly adequate to account for anything ascribed to these 

 parasites. Paulian,^^'^ however, would attribute the chief effect to 

 anaphylaxis from absorbed proteins, while Brincla '''^ believes that 

 ascaris produces an active toxalbumin. This, he found, causes a 

 tetany-like type of respiration, and a similar symptom is often noticed 

 in children with ascarides. An actively toxic mixture of proteoses and 

 peptones has been obtained from several species of ascaris, and desig- 

 nated as "askaron, " by Shimamura and Fujii."'' 



Analysis of a great quantity of ascaris from liorse and liog gave as tlie chief 

 results, the following: ^7 They differ much in composition from the higher ani- 

 mals. About half the ash is water soluble; and of tlie dry substance about half 

 is protein or related substances, from which the usual amino-acids and purines 

 can be isolated. Uric acid and creatinin were lacking. The superficial layer does 

 not consist of chitin, but of an albuminoid rich in sulphur and free from carbohy- 

 drates, resembling keratin. They have abundant and active enzymes of many 

 kinds. Glycogen is the chief carbohydrate, but there are also glucoproteins and 

 gluc^se. The ascaris differs from higher animals especially in the ether-soluble 

 substances, which consist chiefly of free fatty acids, many of which arc volatile. 

 Also found were lecithin, aldehydes and neutral fats, but" little glycerol, no chol- 

 esterol, and an '"ascaryl alcohol'' (C.oHo, 0.) which probably substitutes for both 

 glycerol and cholesterol. 



Trichinella Spiralis has been investigated from the chemical stand- 

 point by Flury,''* who found that the infected nniseles of experimental 



57 Arch. exp. Path. u. Pharm.. ini2 (G7K 275 (literature). 

 57aCompt. Rend. Soc. Biol., 1915 (78), 73. 



57b Arch, de M6d., 1915 (17), SOI. 



57c Japanese Jour. Pact. (Saikingaku Zassi), June 10. 1016. 



58 Arch. exp. Path. u. Pharm., 1913 (73), 164 and 214. 



