on Tetrodontidae and the second on Bothidae and Pleuronectidae (see page 

 232). It is quite possible that this genus must be divided as Price does 

 (Price, 1943b), and then we will have two monotypical genera parasitizing 

 one or two closely related families of fishes; however, the materials of our 

 co-worker L. F. Nagibina (1953) apparently speak against such a division and 

 consequently Heterobothrium is encountered on unrelated families just as 

 Acolpenteron. 



Most interesting are the data about Dionchus . The correlations 

 between the two families of their hosts have already been studied above 

 during the discussion of the hosts of D. remorae (MacCallum) (see page 228 ). 

 However, new data are added to these. Thus, Koratha (Koratha, 1955b) 

 discovered one more species --D. hopkinsi Koratha (a synonym of D. 

 rachycentris Hargis, 1955, nobis)--on the gills of Rachycentron canadus 

 L. (Rachycentridae). In his second work the author (1955a) devotes a whole 

 section to the question of the interrelations between Rennora and Rachycentron , 

 basing himself, as he writes, on the hypothesis of Bychowsky concerning the 

 significance of monogenetic trematodes for the study of systematic relations 

 of the fishes. In this section he expressed in detail the views of a number 

 of ichthyologists on the correlations of both genera (more specifically families)^ 

 and then expressed the data about finding on them representatives of the 

 genus Dionchus. The general conclusion of Koratha is the probability of 

 close relations of both genera, although he indicates that the final solution 

 of this question should be left to experimental ichthyology. We suppose 

 that we can even now speak with a sufficient degree of certitude about the 

 indubitable consanguinity of all three (?) families --host representatives of 

 the genus Dionchus. 



Eight genera of Monogenoidea are indicated as parasitizing four 

 fannilies of fishes (Table 12). There is much that is not clear at the present 

 time in the correlations of species within the limits of these genera, and also 

 with their occurrence on different hosts. 



The genus Axine contains four species encountered on Beloni- 

 formes and one on Carangidae and Triglidae. We did not have the work of 

 Ishii and Sawada (Ishii and Sawada, 1938b) in which the species A. inada 

 from Carangidae (Seriola quinqueradiata Temm, and Schl. ) is described, but 

 according to the data in the work of Sproston (Sproston, 1946) and according 

 to the opinion of Price (Price, 1945) there is no doubt that it is Axine s_. str . p. 257 

 The species from Triglidae, (_A. triglae Beneden and Hesse), was described 

 be Van Beneden and Hesse (Van Beneden and Hesse, 1863) very poorly and 

 even without a drawing. Its true situation is not clear. Thus, it is more 

 probable that Axine is encountered on two families of Beloniformes and on p. 258 

 one of Perciformes, i.e., on two unrelated groups; however, on the first 

 of them in a great number of species and in the second one only singly. 



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