437] PSEUDOPHYLLIDEA PROM FISHES— COOPER 149 



BOTHRIOCEPHALUS OCCIDENTALIS (Linton 1898) 

 [Figs. 28, 89] 



Specific diagnosis: With the characters of the genus. Large cestodes with 

 maximum length at least 310mm. and breadth 5.5. Scolex small, elongate 

 and somewhat rectangular, constricted posteriorly, 1.3mm. long by 0.46 wide. 

 First segments somewhat funnel-shaped; middle, densely crowded, ten to 

 twenty times broader than long; posterior narrower and longer, 2 by 0.8nmi., 

 in groups of three or four. 



Cuticula 1.5/x in thickness. Calcareous bodies 18 by 13ju. Longitudinal 

 muscles in bimdles, outer series very scarce. Four chief excretory vessels, 

 two much more prominent than the others. 



Genital cloacae form a narrow zig-zag row, each very shallow, no velum, 

 cloaca and hermaphroditic duct united. Vagina opens directly behind the 

 cirrus or a little to one side. 



Testes divided into two fields on each side by the nerve strand, 75 to 90 in 

 number, 25, 85, and 115/i in average maximimi length, breadth and depth. 

 Coils of vas deferens loosely arranged, the duct 25/i in diameter, alternating 

 irregularly from side to side opposite the uterus-sac. Cirrus long and cylindri- 

 cal, 0.23 by 0.06mm., walls comparatively thin, most of the circular muscles 

 being towards the inner end. 



No vaginal sphincter nor bulb. Ovary soHd, unbranched, 0.5 to 0.6mm. 

 wide, 0.04 long and 0.13 to 0.18 deep. Oocapt 25/i in diameter. Vitelline fol- 

 licles very numerous, the two lateral fields on each surface narrow, leaving a 

 broad median strip free, 25, 60 and 115/i in length, breadth and depth, respec- 

 tively. ViteUine reservoir 45/x in diameter. Uterine duct voluminous on both 

 sides of the median line, crowding all other organs. Maximum width and length 

 of uterus-sac, 0.65 and 0.25mm., respectively; not encroaching much on neigh- 

 boring proglottides; ventral portion not especially modified. Uterus-openings 

 alternate irregularly from side to side near the median line, far forward in 

 the proglottides. 



Eggs 72 to 76 by 38 to 41/*, dark brown, showing thru the walls of the 

 distended uterus-sacs. 



Habitat: Intestine and pyloric coeca of the "rock cod, " Sebastodes sp. 



Type specimen: No. 4740 in the collection of the United States Museum, 

 collected by T. H. Bean and identified by Professor Edwin Linton. 



Tj^e locality: Whatcomb, Washington. 



The material contained in lot No. 4740 of the coUection of the United 

 States Museum, upon which Linton based his species, was examined by the 

 writer and confirmatory sections were made of mature segments; but it was all 

 in such a very poor state of preservation that only a httle can be added to the 

 meagre descriptions already published. 



