although secondary role; in other words^we do not deny the action of the 

 clamps also as suckers, but this refers to all Diclidophoridae as a whole 

 and is not the basic function of the mechanism of attachment. The study of 

 the actual material of genera- - Diclidophora, Choricotyle , Diclidophoropsis and 

 Heterobothrium serves as a basis for our point of view. One must add that the first 

 2 genera are the most numerous of all the 7 known. 



However, before speaking about the nature of the attaching 

 organs we should make a short survey of their structure among different 

 genera. The study of separate parts of the clamps and other clamps as a 

 whole was made on material fixed in the natural condition and not removed 

 from the gills or other organs of the body of the host. This is very 

 important to our subsequent considerations. The separate parts of the 

 clamps were studied not only and not so much in whole mounts as by means 

 of parts disarticulated from each other and from the musculature in 

 glycerin or glycerin-gelatin with the preservation of their natural location 

 and forna. The clamps of the representatives of the genus Diclidophoropsis 

 are the closest to the initial" discocotylid-type. " In contrast to the 

 indications of Brinkmann (Brinkmann, 1942) and Sproston (Sproston, 1946), 

 who consider the asymmetry of chitinous elements of clamps and the 

 mirror-like (bilaterally symmetrical, nobis) state of the latter on the 

 right and left sides of the body as the basic characteristic peculiarity of 

 Diclidophoridae which enables us to juxtapose it to the rest, in Diclido- 

 phoropsis the structure of the clamps {Fig. 303) is the same on both sides 

 of the body and their chitinous elements have an almost symmetrically 

 mirror structure of the right and left halves. This was first shown by 

 Gallien (Gallien, 1937) who described the present genus and, as a matter 

 of fact, it is also mentioned by Sproston (Sproston, 1946), in spite of the 

 fact that this contradicts her own considerations. The clamp has two 

 unequal plates (sclerites of other workers, nobis) lying along its middle 

 line. The first (Fig. 303, A) the basic and largest, is more or less of the 

 same width along its entire length and lies in such a fashion that its upper 

 T-shaped, widened end comes close to the most exterior edge of the clamp 

 corresponding to the edge of the anterior valve of the clamps of the usual 

 construction. The lower end, also T-shaped and widened, lies approximately 

 in the center of the clamp or somewhat closer to the posterior edge. From 

 this end and articulating with it, the second smaller one extends posteriorly 

 (Fig. 303, B) terminating near the posterior edge of the clamp (near the 

 edge of the posterior "lip") in a small widening. The homology of these 

 plates does not cause any doubt. The first is homologous to the basic plate 

 of Discocotylidae and the second- -to the corresponding plate in Anthocotyle. 

 For the sake of convenience during furtlier comparisons, we shall 

 designate the first plate as basic middle and the second as the supplementary 

 middle. The anterior end of the basic middle plate articulates with two 

 "lateral anterior" plates (Fig. 303, C and D) which extend along the edges 

 of the clamps approximately to its middle where they curve strongly and 

 pass from the edge onto the sphere of the clamp and terminate, articulating p. 433 



518 



