^ 



tl' 



3A' 



Rhamnocercinae (see page 356). 

 One cannot doubt that this is a con- 

 verging similarity, but the fornnation 

 of analogous peculiarities in different 

 systematic groups is interesting 

 (see page 464 ). 



Let us note also that for 

 Monocotyle and Heterocotyle the 

 presence of middle hooks of the so- 

 called dactylogyrid-type is charac- 

 teristic, i. e. , --with two extensions 

 of which the exterior is larger than 



Fig. 275. Spinuris lophosoma Doran, 

 adult wornn. According to Doran, 

 1953. 



Fig. 276. Hooks of Monocotylidae. 

 A--monocotylidae-type; B--dasy- 

 batotre mid -type. 



the interior (see Fig. 276, A). Conversely the middle hooks among 

 Spinurus are of dasyabototremid-type (see below). This circunastance, 

 a determined form (or common shape, nobis) of the hooks is 



important in the establishment of the relations among Monocotylinae and 

 subsequent subfamilies, as one of the most important characteristics. 



2. Subfamily Dasybatotreminae Bychowsky, subfam. nov . 



(Figs. 32, I, 80, B, 274, C) 



Monocotylinae Gamble, 1896, part . 



Monocotylidae having an attaching disc with a central depression 

 and 7 peripheral ones delimited fronn each other by muscular septa. The 

 anterior end has a subterminally located, weakly expressed, adoral 

 sucker and a number of cephalic glands opening along the anterior edge. 

 The eyes are absent (?). The vaginal duct is single. The testis is single, 

 it is rounded. 



438 



