605 



determination of Zedei-Ruolplii's species, but ignored syn- 

 onymy prior to Zeder. Thus we have no way of knowing 

 whether the form now named sinuosa is identical with the 

 original sinuosa or not, and Dujardin is the earliest author to 

 whom we can trace the present sinuosa with any degree of cer- 

 tainty. Authors generally follow Krabbe in accepting Dujar- 

 din's determination of Zeder's sinuosa and it will be well at 

 present to adopt this plan. 



The views concerning the life history of this worm rest upon 

 observations by Hamann, Mrazek, and von Linstow. Hamann 

 (1889, pp. 1-7, Taf. I) found some cysticercoids in Gammarus 

 pulex which von Linstow determined as the young of T. sinu- 

 osa. They were oval to spherical; tail surrounds body as a 

 yellowish border; 6 oncospheric hooks, 13 /^ long, persistent, 

 one pair at end, one in middle, and one at beginning of tail; 

 tail 0.5mm, body with tail 1.3mm long; hooks of cysticercoid 50 

 u long, 10 in number; calcareous bodies numerous, 6 ;* in diam- 

 eter, oval. Mrazek found a cysticercoid in Bohemia, 0.23miii 

 long; tail moderately long, oncospheric hooks 11 /*; 50 calcare- 

 ous corpuscles present. He identified this organism with Ha- 

 mann's larval form, and records it from Cyclops virdis Fisch, 

 C. agilis Koch, and C. lucidulus Koch. So far as I can learn 

 no infections were made with these parasites. 



15. DREPANIDOTAENIA SETIGERA (FroUch, 1789) UaiUlet, 1893. 



(1789, Taenia setigera Frolich; 1800, Alyselminthus setigerus 

 (Frolich. 1789) Zeder; 1803, Halysis setigera (Frolich, 1789) 

 Zeder; 1819. "Taenia sinuosa Rud.," 1810, of Rud., pars.— vide 

 Krabbe, 1869; 1848, "T. setigera Frolich," 1789, of Siebold; 1858, 

 T. fasciata Rud.," 1810, of Feuereisen; 1869, "T. setigera Fro- 

 lich" of Krabbe.) 



[PI. XII, figs. 147-150; PI. XIII, figs. 154-164.1 



Diagnosis: Strobila 200mni long by 1mm to Jmm broad. Head 

 subglobular, 0.24mm long by 0.2Smm to 0.33mm broad; rostellum 

 with simple crown of 10 hooks 35 // to 43 /* (40 /* to 60 /^ long, 

 prong 20 ft long, roots 20 fi apart, after Feuereisen); ventral 

 root short and plump, dorsal root longer. Suckers rather large, 

 elliptical. Neck, 0.59mm long by 1.16mm broad. (Segments very 

 short, 10 times as broad as long, Feuereisen.) Anterior seg- 

 ments very short, the following slightly longer, tunnel shaped, 

 with very prominent posterior angles; chain traversed by a 

 dark median band. Pores unilateral, small, situated tovvjir.l 

 anterior angle of the segment, frequently with extruding penis. 



