on the attaching disc would be hardly correct because in the drawing of 

 Palombi (Palombi, 194Zb, Fig. 1) the presence of the festoon-shaped 

 fringe, which is not characteristic for the present subfamily but which 

 occurs in Megalocotylinae and Trochopodinae among the groups having 

 3 pairs of middle hooks, is clearly visible. In connection with what has 

 been said, we do not consider it possible at the present time to attribute 

 Ancyrocotyle to any subfamily of Capsalidae, until receiving completely 

 trustworthy data about the independence of the genus and of a more detailed 

 study of its morphology. 



5. Family Acanthocotylidae Price, 1936. 



Monopisthocotylinae (sic), having middle or small sizes in the 

 adult state. The attaching apparatus consists of a primary attaching disc 

 armed with 14 edge and 2 middle hooks of the same shape and sizes. Along 

 with this, the adult forms, with the exception of Enoplocotyle, have a large 

 secondary disc lying above the first and armed by a considerable number 

 of special thorns situated in radial rows. As an exception, these thorns 

 can be absent and in their places there are muscular septa. The anterior 

 end of the body with two contractile outgrowths forming sucker-shaped 

 depressions with festoon-shaped edges for the most part. The eyes are 

 absent. The intestines are 2-branched with smooth trunks or forming 

 snaall outgrowths; as a rule the latter terminate blindly. The male sex 

 aperture lies behind the pharynx between the branches of the intestine. 

 The copulatory organ is unarmed or armed. The testes are numerous or 

 there can only be one. The ovary is round. The opening of the uterus is 

 on the side of the body. There is no vaginal duct. 



Parasites of marine Elasnnobranchii, Muraenidae and Nototheniidae 



The structure of the primary attaching disc, which beyond any 

 doubt corresponds to the disc of the larva emerging from the egg, is 

 characteristic for the fanaily. This is beyond doubt although the develop- 

 ment of Acanthocotylidae has not been studied. For all the worms which 

 relate to this family the presence of 16 chitinous attaching hooks, of which 

 14 are located along the periphery of the primary disc and are undoubtedly 

 homologous to the edge hooks of the remaining monogenetic trematodes, is 

 characteristic. As regards the two hooks lying in the middle of the disc, 

 the question about them is not altogether clear. Morphologically it does 

 not seem possible to differentiate them from the edge hooks and in this 

 connection they can be interpreted either as edge hooks which took up the 

 central position on the disc or as actual middle hooks. In the first case 

 the ancestors of the family must be sought among the lowest forms which 

 have 16 edge hooks^ while the second--among those equipped with 14 hooks. 

 It is unlikely that such could be l6-hooked Gyrodactylidae, for the copulatory 



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