451] PSEUDOPHYLLIDEA FROM FISHES— COOPER 163 



of the cirrus and vagina pierce the cuticula in development. Behind this 

 region it was found impossible to trace the main vessels with satisfaction. The 

 system usually passes into the scolex as two vessels, but soon breaks up into 

 an elaborate net-work which ramifies between the bothria and throughout 

 their walls. These branches are shown in Johnstone's figure 15. As regards 

 the conditions of the excretory system in the extreme posterior end of the 

 strobila, the material at hand permits of only negative conclusions. In the 

 youngest strobilas, such as that shown in figure 49, the vessels converge pos- 

 teriorly to open into a notch in the cuticula, there being no definite terminal 

 vesicle such as is presen*- in plerocercoids of the genus Proteocephalus, for 

 instance. From this and the further fact that Wagener (1857:93) showed 

 (Fig. 6, PI. II) the main vessels in a very small strobila, which he examined 

 while it was alive, passing separately to the outside, one is led to conclude that 

 the vesicle, if ever present, must have been situated in the walls of an envelop- 

 ing cyst and disappeared with the latter as in the Trypanorhyncha or the 

 Cyclophyllidea. This seems to have been Wagener's idea of the situation 

 when under his figure 65 (1854:68) he said: "Man sieht keinen pulsirenden 

 Schlauch am spitzen Schwanzende. Es muss dies Thier auf ahnliche Weise 

 entstanden sein, wie das in Fig. 74 dargestellte, " and figure 74 is that of "Di- 

 bothrium (Belones ?)" from Scyllium canicula enclosed in a cyst in the walls 

 of which "man sieht die Gefasse der Cestodenblase. " 



The earliest reference to the genitaHa of C. crassiceps was by Rudolphi 

 (1819:477) who said: 



"Ova vel ovaha vel ovata, forsan secundun majorem maturitatis gradum. 

 A B. punctato diversissimus, licet ovaria lateralia fuscescant, sed haec ipsa 

 etiam in B. crassicipite quam in B. punctato majora sunt." 



The structures called ovaria were evidently the uterus-sacs. F. S. Leuck" 

 art (1819:46) described the reproductive organs of his B. pilula as follows: 

 " . . . die letzte Half te der GHeder breiter als lang, mit deutlichen, weissen ovar- 

 ien. An den unteren Gliedem sieht man oberhalb jedes Eierstockes einen was- 

 serhellen Punkt, wahrscheinlich Oeffnung fur das mannliches Zeugungsglied." 

 From a comparison of this with his description and figure of posterior proglot- 

 tides of B. scorpii, it is evident that he too was dealing with the uteri and their 

 openings, respectively. He also referred to ". . . den schwarzen Punkten 

 des Korpers, die Rudolphi fur Ovarien gehalten" of Redi's worm, which Rudol- 

 phi called (1810:67) Bothriocephaliis gadi merluccii and placed in his "Species 

 dubiae." Wagener (1854a:61) said that "Die Eier haufen sich in obersten 

 Theile der Glieder an. Der Dotterstock verzweigt sich uber das ganze Glied 

 und liegt overhalb der vescicules transparentes van Beneden. Die Gesch- 

 lechtsoffnung ist in der Mitte und lateral." Diesing (1863:236) placed the 

 "Aperturae genitalium laterales in linea mediana." Ariola (1896:265-266) 

 gave the first comprehensive description of the reproductive organs in the 

 following words: 



"Tuttaria sul corpo si osservano macchie scure molto sporgenti, constituite 

 della massa die uova. Tali riUevi non sono propriamente, nella linea mediana, 



