clamps and 2 pairs still in the process of development. The "larval 

 attaching disc" with its middle and edge hooks is already absent by this 

 stage of development. ^ 



1 



Supplement to the proofreading. In November, 1955, the work of 

 Frankland /(Helga M. T. Frankland). "The life history and bionomics of 

 Diclidophora denticulata (Trematoda: Monogenea). Parasitology 45, 3-4: 

 313-351/, in which is described in detail the development of^ denticulata 

 starting from the development of eggs and terminating with the post- 

 embryonic development on the gills of the host, appeared in print. The 

 data of the author concerning the free -swimming larva coincide with ouis 

 with the exception that according to Frankland the general sizes of the 

 larva as well as of the hook apparatus are two times smaller than the 

 ones observed by us (see page 198 ). The reasons for this are not clear 

 to us, however, judging by the drawing of Frankland the larvae were 

 examined by her in fixed shape which probably caused the minimization 

 of the true numbers (mieasurements, nobis) . The subsequent stages of 

 development described by Frankland are analogous to the ones observed 

 by us in Microcotylidae (see page 210) and do not require special remarks. 

 The remarks of Frankland concerning "ciliary larva" ( loc. cit. , pages 338- 

 346), in which she indicates all the literary data known to her about free- 

 swimming larvae are interesting. These data are reproduced in the 

 corresponding places of the present appendage. It is noteworthy that the 

 structure of the larva causes Frankland to indicate that there are two 

 types of larvae , to the first of which are related the larvae of Monoplstho- 

 cotylea and Polystomatoida from Polyopisthocotylea and to the second- - 

 only Diclidophoridea (should this be the superfamily -oidea?, nobis ) 

 (Polyopisthocotylea), i.e., the author unwillingly comes to the same 

 inferences as we without drawing the corresponding conclusions from it. 



236 



