CESTODES 197 



4. PHYLLOBOTHRITJM van Beneden. Bothria sessile or nearly so, 

 with very convoluted edges and with an anterior accessory sucker; neck 

 very long: several species. 



P. f oliatum Linton. Length up to 18 cm. ; length of 

 terminal segment about 1.4 mm., width .9 mm.: often 

 numerous in spiral valve of the sting ray. 



5. ECHENEIBOTHRIUM van Beneden. Bothria stalked, 

 elongate or oval, and very contractile, the face of each 



Fig. 319 



being subdivided by 1 or 2 longitudinal and several trans- Scolex of 



Echeneibothriuw, 



verse septa; myzorhynchus present but may be wanting in vaHdbUe 

 . (Braun). 



old worms: several species. 



E. variabile v. Ben. (Fig. 319). Length about 10 cm.; neck long: 

 in the spiral valve of the common skate; often common. 



ORDER 3. CYCLOPHYLLIDEA. 



Body usually elongate; scolex with 4 simple cup-shaped suckers, 

 between which a protrusile rostellum with hooks is usually present; 

 segmentation distinct; no uterine pore; common genital pore usually 

 marginal; yolk gland unpaired and usually behind the paired ovary: 10 

 families and about 50 genera which live principally in the higher verte- 

 brates; larva a cysticercus or cysticercoid, so far as known. 



Key to the families of Cyclophyllidea here described: 



di Uterus transverse in position and either tubular, sac-like, or reticulate. 



& x Scolex without hooks 1. ANOPLOCEPHALIDAE 



& 2 Scolex with hooks. 



c v No hooks in the suckers 2. DIPYLIDIIDAE 



c 2 Suckers armed with hooks 3. DAVAINEIDAE 



a 2 Uterus consists of a median stem and side branches 4. T^ENIIDAE 



FAMILY 1. ANOPLOCEPHALIDAE.* 



Scolex more or less spherical, without hooks but with large suckers; 

 segments short and wide; uterus transverse in position and tubular, sac- 

 like, or reticular: in mammals; 8 genera. 



Key to tKe genera of Anoplocephalidae here described : 



<H Genital pore on but one side of the segment. 



&! Genital pores on the same side of all the segments 1. AXOPLOCEPHALA 



& 2 Genital pores regularly or irregularly alternate 2. BERTIA 



a 2 Genital pores on both sides of the segment. 



&! Uterus reticulate and double 4. MONIEZIA 



& 2 Uterus tubular. 



G! Uterus a thick tube, single or double : in rodents 3. CITTOT^ENIA 



c s Uterus undulate : in sheep 5. THYSANOSOMA 



* See "A Revision of the Adult Tapeworms of Hares and Rabbits," by C. W. 

 Stiles, Proc. U. S. Nat. Mus., Vol. 19, p. 145, 1896. 



