303] PSEUDOPHYLLIDEA FROM FISHES— COOPER 15 



DIPHYLLOBOTHRIIDAE Liihe 1910, char, emend. 



Polyzootic Pseudophyllidea with unarmed or (seldom) armed scolex. Sur- 

 ficial bothria variously developed; they may be modified to form sucking 

 tubes, each with an anterior and a posterior opening, thru the growth together 

 of their free edges, or an unpaired terminal organ of attachment can serve as a 

 functional substitute for the rudimentary bothria or result from the more or 

 less complete fusion of both bothria. The whole scolex may be replaced in 

 sexually mature specimens by a pseudoscolex; or it may be (Haplobothriinae) 

 provided with four protrusible proboscides. Neck present or absent. Exter- 

 nal segmentation mostly present, seldom absent. Genital organs numerous, 

 mostly single in each proglottis, seldom double. Cirrus unarmed (excepting 

 in Haplobothrium), with cleft cuticula. Opening of cirrus and vagina surficial 

 or marginal; in the first case always on the same surface as the uterus opening 

 and ahead of this as well as always in the median line of the genital complex, 

 also in the median line of the proglottis in the case of single genitalia. Both 

 surfaces of the chain of proglottides, apart from the genital openings, similarly 

 shaped. Receptaculum seminis formed by a local enlargement of the vagina 

 near its inner end, which as a rule is sharply separated from the spermiduct 

 (terminal portion of the vagina). Uterus, a long, more or less winding canal, 

 usually in the form of a rosette, f6rmed by almost transversely directed coils 

 crossing the median line. It may be locally more or less enlarged, but seldom 

 forms an undivided uterus-sac distinct from the uterine duct, as in the Ptycho- 

 bothriidae. Eggs thick shelled, with opercula, excepting in the Marsipome- 

 trinae; their formation is carried on continuously in fully-developed proglot- 

 tides; embryonal development takes place usually after liberation, seldom in 

 the uterus, in which case, however, all stages are found side by side. 



Parasites of vertebrates. 



Liihe's (1910:16) diagnosis is here emended to include the new subfamilies 

 Haplobothriinae and Marsipometrinae. In the former not only is the scolex 

 radically different from that of any other member of the family, but the cirrus 

 is armed with minute spines and there is a distinct uterus-sac, separate from 

 the uterine duct as in the Ptychobothriidae; while in the latter there is likewise 

 a uterus-sac and the eggs are not provided with opercula. The cirrus of 

 Haplobothriurn, however, would seem to exclude the genus from the family 

 Ptychobothriidae as well as from the Diphyllobothriidae, smce it is not "un- 

 armed, with cleft cuticula, " but provided with minute yet distinct cuticular 

 spines bearing some resemblance to those of the Acanthophallidae ( Amphi- 

 tretidae), as pointed out elsewhere by the writer (1914:3). But H. glohidi- 

 fortne is otherwise so nearly related to Diphyllobothrium latum that it does not 

 seem wise to remove it from the family on this account, especially since these 

 spines are so minute and since the evidence points to their being probably of 

 little, if any, functional importance. The uterus on the other hand is quite diff- 



