1 



Should this turn out to be true, it will be necessary to bring the genus 

 Lithidocotyle near to Gotocotyle with corresponding conclusions. 



The presence of only one pair of middle hooks in all species 

 attracts attention. This is undoubtedly a very important characteristic 

 which shows a considerable difference of this genus from Microcotyle, 

 even in case this genus should remain in the present family. The genera 



OOlflH 



•t- 



Fig. 309. Microcotyle mormyri Lorenz from the gills of Pagellus mormyrus 

 (L. ) from the Bay of Naples (Mediterranean Sea). A- -Normal clamps from 

 the right and left halves of the posterior part of the attaching disc; 

 B- -Asymmetrical clamps of the anterior part of the disc. 



Microcotyloides and Gonoplasius , representatives of which we did not 



have, closely approach Microcotyle , in connection with which w^e cannot 



evaluate their independence with certainty. Nevertheless in all probability 



the separation of the first genus is fully founded because the presence of 



the lateral opening of the single vaginal canal is a sufficiently important p. 442 



characteristic. As regards the second, in spite of the long diagnosis of 



the author (Sandars, 1944a) the differences from Microcotyle practically 



can only be summed up by the presence of a large number of glandular cells 



of the anterior end of the body which hardly appears sufficient, as Sproston 



correctly points out (Sproston, 1946). 



In the further process, the presence of the differentiation of the 

 attaching apparatus, similar to the one which is observed in M. mormyri 

 Lorenz, leads to the fornaation of species with the sharply expressed two 

 types of clamps. Their first part, incepted earlier, retains discocotylid 

 traits, whereas the second becomes completely different. We observed 

 a corresponding structure of the clamps in two genera Pyragraphorus and 

 Cemocotyle , which were quite correctly separated by Sproston (Sproston, 

 1946) from the genus Microcotyle , s. str. The first genus is 

 characterized by the fact that the modified clamps acquire a long "handle" 

 which acts as a spring and resembtes very much a waffle iron in appearance 

 and the second by the growing and elongation of the customary elements of 



529 



