the morphology of representatives of both genera is accomplished. As 

 regards the genus Neodiplectanum, its description is very fragmentary 

 and is clearly insufficient. What is interesting here is the fact that the 

 authors described two connecting plates. This undoubtedly would have 

 substantiated our views on the origin of the typical structure of the 

 attaching apparatus of Diplectanidae ; however, the drawings in the work 

 of Mizelle and Blatz (Mizelle and Blatz, 1941) are such that we suppose 

 that there is a possibility of error in their assertions. Among the species 

 of Diplectanum which are at our disposal there are some that possess a 

 middle plate of such length that it reaches both pairs of connecting hooks 

 (middle hooks, nobis), and both lateral connecting plates are so tightly 

 pressed against the middle one that on cursory examination it seems that 

 there are only 2 and not 3 plates. Judging fronn the drawing of Mizelle and 

 Blatz, this error is also not excluded in their case. If this be so, the genus 

 Neodiplectanum has absolutely no right to independent existence. In con- 

 nection with what has been said in the diagnosis of the family and sub- 

 family, the smaller number of connecting plates is indicated with a question 

 mark. 



The genus Lamellodiscus is undoubtedly very close to 

 Diplectanum, its attaching armature appears as if it were the next step 

 in the process of fusion of the separate little parts of the ring of chitinous 

 elements of the supplementary disc. 



As regards the genus Lepidotrema.it was already indicated that p. 359 

 it stands somewhat apart from the rest of Diplectaninae. 



The status of the genera Diplectanocotyle and Pseudolamellodiscus 

 is not clear to us (see note on page 349). 



2, Subfamily Rhamnocercinae Monaco, Wood and Mizelle, 1954 



(Fig. 272) 



"Diplectanidae : the attaching disc is equipped with large thorns 



The authors here give "Dactylogyridae" instead of "Diplectanidae. " 



divided into separate groups, but not forming supplementary discs; there 

 are two pairs of middle hooks (dorsal and ventral) attached by their bases 

 to the middle plates; the edge hooks exist. The "stem" of the attaching 

 disc is equipped with rows of thorn-shaped hooks. Eyes are present. The 

 testes and the ovary are entire, the ovary lies in front of the testes, " 

 Monaco, Wood and Mizelle, 1954. 



426 



