animals (Dubinin, 1951, 1954). Exceptions are fornr>ed only by J. D. 

 Kirchenblatt and G. S. Markov. The first of them, in the very interesting 

 and little used--although often criticized work about the specificity of 

 parasites for their hosts, indicated that specificity is a characteristic 

 attribute of each species of parasite, that is, it represents a specific 

 character (J. D. Kirchenblatt, 1941). This is more clearly expressed by 

 G. S. Markov in his above-mentioned dissertation. We consider this 

 completely correct and,- as we shall attempt to show further., it should be 

 constantly borne in mind by parasitologists during their evaluations in determining 

 to which systematic categories a particular parasite should be ascribed. 

 However, one must warn about excessive positivism (or reliance on, 



nobis) of this nature which can lead to metaphysical distortions charac- 



teristic of the thinking of a number of foreign parasitologists, the most 

 obvious representative of whom is Szidat (Szidat, 1944). A just critique p. 286 



of the conceptions of Szidat has already been given by a nunnber of Soviet 

 researchers (Markov, 1948; Dubinin, 1951; Shulmann, 1954b). 



The question about the process of the development of specificity 

 of parasites to their hosts is extremely important. In order to understand 

 it, it is first of all indispensable to analyse the historical origin of the bio- 

 coenotic pair, parasite-host. 



The nature of the origin of the pair, parasite -host, in the given 

 historical period of time is touched upon in a well-known article by E. N. 

 Pavlovsky, "Conditions and factors of the establishment of the parasite in 

 the host organism in the process of evolution" (1946).* 



♦Editor's Note 



The precise translation of this passage is somewhat different 

 from the interpretation given here and elsewhere, and Bychowsky may have intended 

 a slightly different meaning. Literally, it is translated: "Conditions and factors 

 of tiie formation of the organism of the parasite by the host in the process of evolution. " 



Bychowsky may have meant to indicate that the host or rather 

 the milieu offered by the host had something to do with the evolution of the 

 parasitic organism or of the biological entity (organism?) which the host- 

 parasite is: Which, of course, it did. However, in English the phrase, 

 "formation of the organisnn of the parasite by the host. " is awkward and 

 somewhat unclear; therefore, we have translated it as above with the full 

 realization that our translation may not catch an intended nuance of 

 meaning properly. Places where this phrase occurs below are marked 

 with a double asterisk. 



328 



