485] PSEUDOPHYLLIDEA FROM FISHES— COOPER 197 



them as being between the uterus and the marginal nerves as in B. imbrkatus. 

 In the present study they were found to pass to the median line and dorsal 

 to the uterus-sac in the anterior portion of the proglottis but to be prevented 

 from doing so posteriorly by the ovary and the ducts in its immediate neighbor- 

 hood. They are not all in the same horizontal plane but arranged in two or 

 three pseudostrata (Fig. 92). Their number is from 40 to 150 in each proglottis 

 with an average of 90, and their dimensions from 95 to 115/i in depth by 70 

 to 100 in transverse diameter, being roughly circular in frontal sections. The 

 vas deferens forms an elongated mass of coils of quite the same shape and ar- 

 rangement with the fewer coils before entering the cirrus-sac as in yl. rugosum. 

 Its dimensions are 0.35 to 0.60 by 0.15 to 0.18mm. In the proximal one-third 

 to one-half of the cirrus-sac the male duct forms a mass of coils, the ejaculatory 

 duct, which may or may not become enlarged with sperms to form at least a 

 temporary inner seminal vesicle, while in the distal half of the pouch it con- 

 tinues in an almost straight course as the cirrus proper with a maximum dia- 

 meter of 20a£. The cirrus-sac varies in dimensions from 130 to 220 by 60 to 

 105)U in the fresh-water form and 255 to 380 by 120 to 150/x in the form from 

 Salmo salar, and is ovoid in shape with the smaller end, often quite pointed, 

 towards the genital cloaca. Matz gave the length of the cirrus-sac as 255fi 

 for the form from the European salmon and salmon trout. The wall is com- 

 paratively thinner and there are fewer parenchymatous nuclei around it or 

 within it among the conspicuous retractor muscles than in A. rugosum. 



The vagina opens constantly ahead of the cirrus and more or less ventral 

 to it as pointed out by Matz (p. 112). From this point it bends backward 

 and gradually downward, thus making a bow which lies below the coils of the 

 vas deferens, and then courses mediad parallel to the anteroventral border of 

 the latter. Near the median line, however, it again rises to pass over the lateral 

 border of the ovary before gaining the oviduct. There is thus a broad ventral 

 bow to the vagina, which, contrary to Liihe's statement, is more median than 

 in A . rugosum. Opposite the cirrus-sac the vagina may be found enlarged to 

 a diameter of 35yu. The ovary is quite irregular or only very roughly kidney- 

 shaped as stated by Liihe (1900a), and has a maximum diameter in the marine 

 form of 0.8mm. by a length of O.lSmm.. As in yl. rugosum, there is a very 

 broad isthmus, with the posterodorsal part of which the oviduct is connected by 

 the oocapt which has a diameter of 40ju. The oviduct receives the vagina 

 in the median coronal plane. Usually two small vitelUne ducts passing along 

 the ventral floor of the medulla unite in the median line to form a common 

 duct v/hich is not enlarged to form a reservoir; but in the material from Lota 

 two others were seen to unite dorsally to form another common duct, while 

 the ventral duct formed a number of anastomoses with its tributaries before 

 uniting with the oviduct. Matz described the vitelline follicles as irregular in 

 shape, discontinuous from proglottis to proglottis and located among the longi- 

 tudinal muscles, there being about 29 "on the surface," presumably in trans- 

 verse sections. The writer likewise found them to be quite irregular in shape and 

 to range in location from among the inner longitudinal muscles to distinctly out- 



