96 ENTOZOA. 



allied to the previous family, but tlie characters relating to the 

 mouth, coupled with the absence of a true bursa, seem to justify 

 theu^ separation into a distinct family. At all events, it is conve- 

 nient to consider them apart. In the majority the body is cylin- 

 drical, obtusely rounded or truncated in front, and attenuated 

 posteriorly ; head broad and globose, in consequence of a strong 

 muscular mass surrounding the pharynx, the latter being usually 

 bivalvular ; mouth seldom round, terminal or subterminal, opening 

 vertically or transversely by a slit ; tail of the male recurved and 

 slightly coiled, sometimes truncated and usually furnished with 

 membranous winged appendages ; a pre-anal sucker occasionally 

 present. 



Genera. — Cucullanus, Miiller; Angiostoma, Dujardin; DacnitiSi 

 Dujardin ; Pleurorhynchus, Naudyn ; OpJdostoma, Rudolphi ; = 

 Frohoscidea, Bruguiere ; Bictularia^ Frohch ; = Fissula, Lamarck ; 

 Hedruris, Nitzsch ; Synjtlecta, Leidy ; Stelmius, Dujardin. 



