NO. 1105. PROCEEDINGS OF THE NA TIONA L MVSE UM. 187 



longitudinal canals; the cirrus pouch is deserving of special notice. In the majority 

 of the known Tseniidte the cirrus pouch is pyriform and rarely extends median of 

 the ventral canal, but in C. pectin ata it is a long narrow structure reminding one 

 of the noxzle of a hose; Riehm gives its average length as more than 1 mm., and on 

 Plate VI, fig. 4, shows that it is more than twice as long as the distance between the 

 genital pore and the longitudinal canal. This extreme length of the pouch is a 

 character of great importance. Female organs: The vagina, according to Riehm, is 

 about as large as the cirrus pouch. At a point corresponding to the proximal end 

 of the cirrus pouch it becomes suddenly very thin, and leads to a second swelling, 

 the receptaculum seminis. The female glands correspond in all essential characters 

 to those of the genus Moniezia, except that the ovary is described as composed of 

 two quite distinct halves. Their position, some distance from the longitudinal 

 canals, is striking. The uterus is said to be similar to that of C. ctcnoides, namely 

 "a common uterus for both sides, which extends the entire breadth of the segrnen, 

 and is constricted only in the middle, so that in the gravid segments the lateral 

 portion appears swollen by the ova in comparison with the rather thin median 

 portion. Its volume is also considerably increased laterally [namely, laterally to 

 the uterus, longitudinal in reference to the worm] by apparently uubranched tubes 

 which extend anteriorly and posteriorly. As a matter of fact, however, these tubes 

 resolve themselves as the optical sections of a corresponding number of circular 

 wideniugs of the uterus." Excretory system: The dorsal canals become obliterated 

 some distance from the head. The transverse canals are connected with one another, 

 not only by the ventral canals, but also by numerous smaller longitudinal canals. 

 Topographically, Riehm figures the genital canals as dorsal of the nerve and longi- 

 tudinal (ventral) canal. The parasite is said to occur only in the fall and first half 

 of the winter, and only in hares. It was especially common around the Roblinger 

 See, but rare on the higher plateaux of Saxony. 



Blanchard 1 in 1891 states that he found this species in several hares 

 of unknown origin. He has never found it in hares in the central part 

 of France or around Paris, but found four specimens at Briancon in 

 Lepus variabilis, killed at a height of 1,500 meters. His description, 

 based upon these specimens, may be summarized as follows: 



The largest specimen was 18 cm. long; maximum breadth, 7 to 10 mm. ; head 315 to 

 340 /it broad ; neck, 285 to 325 jti broad ; in contracted specimens the neck may measure 

 1 mm. broad at the first segment; suckers elliptical, 142 // long by 135 JLI broad; 

 opening, 80 // long by 53 // broad ; mature segments, 7 to 10mm. broad by 1.1 to 2mm. 

 long; penis smooth, 40 to 45 f.i in diameter, extrudes 175 to 200 u from pore; eggs 

 generally polygonal from reciprocal pressure, but become elliptical or subspherical 

 when pressure is removed; 80 to 90 JJL by about 75 /.i ; outer membrane 1 to 2 u thick; 

 diameter of bulb of pyriform body 25 to 30 JLI ; length 40 to 50 JLI ; horns terminate in 

 a long filament; hooks of oncosphere 8 ju. 



Railliet 2 in 1893 places this species in his genus Ctenotwnia. 



Through the kindness of Dr. Brandes, I have obtained one of Riehrn's 

 original specimens of Dipylidium pcctinatum for comparison with the 

 American forms, and Blanchard has placed his forms from L. variabilis 

 at my disposal. In my private collection I find several specimens ot 

 tapeworms from Lepus tlmidus which I collected in Leipzig in 1890, and 

 which agree perfectly with Rielmrs form. With this material at hand, 

 together with one specimen from von Linstow and several from Moniez. 



'Mem. Soc. zool. France, IV, pp. 445, 452, 457-460, figs. 26-30. 

 2 Traite Zool. uied. et agric., I, pp. 278-279. 



