424 Journal of Agricultural Research voi. xxn.No. s 



and his collaborators) , and in several other species by the present writer 

 {tq2i.) The anticoagulin in Ancylosioma caninum is the most active of 

 the anticoagulins observed in parasitic worms and is doubtless a factor 

 in the anemia that is present in hookworm disease. The anticoagulin of 

 Ascaris lumbricoides has but a feeble action, so far as available experi- 

 mental data show. 



Hemolysins from parasitic worms, so far as they have been described 

 in the literature, have certain properties in common with hemolysins of 

 bacterial origin as well as with hemolysins that have been obtained from 

 normal tissues by Korschum and Morgenroth, Noguchi, and others. 

 These properties may be characterized as nonspecificity in action and 

 relative simplicity of structure as compared with hemolysins that may 

 be artificially produced in animals by immunization with red blood 

 corpuscles. The experiments recorded in this paper do not in any case 

 contradict these facts. Different species of blood corpuscles may show 

 differences in resistance to hemolytic extracts of parasitic worms, but 

 absolute resistance of any species of corpuscles has not been established. 

 Similarly, extracts from different parasitic worms differ in their resist- 

 ance to heat, but once their potency has been destroyed it can not be 

 reactivated by normal serum. The only apparent contradiction to this 

 statement is the result of a small series of experiments of Garin with 

 Graphidium sirigosum, which, as has already been indicated, can not 

 be accepted as conclusive in view of the small number of experiments. 

 Hemolysins produced in an animal as a result of immunization with 

 red blood corpuscles, are, as is well known, specific in their action, 

 affecting only corpuscles against which the animal has been immunized, 

 and complex in structure, since they act in combination with comple- 

 ment and may be reactivated by normal serum after the complement 

 has been destroyed. 



So far as their resistance to heat is concerned, hemolysins from para- 

 sitic worms differ considerably. Heat-resisting hemolysins have been 

 recorded by Tallqvist from Diphyllobothrium latum, by Weinberg from 

 species of Strongylus, and by the present writer from Ascaris lumbricoides 

 and Thysatiosoma actinioides. Hookworm hemolysins from worms of the 

 genera Ancylostoma, Necator, Bustomum, and the hemolysin from Tri- 

 churis depressiuscula are not as resistant to heat. The relatively thermo- 

 labile hemolysins from these parasites resemble in this respect bacterial 

 hemolysins, whereas the thermostabile hemolysins resemble in this respect 

 tissue extracts. 



The solubility of hemolysins from parasitic worms in lipoid solvents, 

 especially in alcohol, is another property that they have in common with 

 tissue lysins. A property of the latter is also the nonimpairment of their 

 activity at low temperatures, even at 0° C. So far as the results of 

 experiments recorded in this paper are concerned, hemolysins from 



