For Mugiliformes, the presence of Dactylogyridae, Gyro- 

 dactylidae and Microcotylidae is known. On them parasitize the repre- 

 sentatives of the genus Ancyrocephalus from Dactylogyridae, from 

 Diplectanidae--Diplectanum, from Gyrodactylidae- - Gyrodactylus (on 

 Atherinidae), from Microcotylidae the worms of three genera- - Micro - 

 cotyle, Metamicrocotyle, and Diplasiocotyle , and from Gastrocotylidae-- 

 Chauhanea (on Sphyraenidae). One can consider that, without exception, 

 the parasites of Mugiliformes are phylogenetically secondary for thera, 

 having transferred predominantly from Perciformes (for Mugilidae and 

 Sphyraenidae) and possibly from Cypriniformes (for part of Atherinidae). 

 Inasmuch as Mugiliformes are very close to Perciformes (Suvorov, 

 1948);this does not occasion any doubt. 



Only one species of Microcotyle is known on Polynemi- 

 formes. It transferred to this group either from Perciformes or 

 perhaps from Mugiliformes, closely related to this order. In both 

 cases the transfer took place relatively recently, because the special 

 species M. polynemi MacCallum which is isolated on Polynemus 

 auratus is very close to the typical Microcotyle. 



So far only one species of Gyrodactylus which transferred, p. 314 

 without any doubt, from fresh water Perciformes or, it is even more 

 probable, from Cypriniformes of the far East (Gussew, 1955), is known 

 on Ophiocephaliformes. 



The fauna of monogenetic trematodes of Perciformes is 

 the richest. Representatives of 17 families parasitize these fishes, 



I 



The indication of the finding of Acanthocotylidae on Perciformes 

 is apparently erroneous (see page 275 ). 



and five of them are not discovered on any other fishes (they are marked 

 in Table 7 by an asterisk). In addition to that, five are discovered on 

 one order of fishes each and seven--on two and more orders. Among 

 the first group there are families containing only one or two genera, 

 narrowly specialized to parasitizing one genus of hosts --they are 

 Tetraonchoididae (see page 394 ) and Protogyrodactylidae (see page 359 K 

 The remaining families have somewhat larger distributions which is 

 apparent from Tables 16 and 17 and also from, the corresponding text 

 (see page 265 and further). 



365 



