174 TAPEWORMS OF HARES AND RABBITS STILES. VOL.XIX. 



rostellum not visible. Keck absent, segmentation beginning immedi- 

 ately back of the head, the proglottids rapidly becoming distinct; 

 segments vary in length from 56 /t to 0.75 mm., and are always much 

 broader than long, measuring in some cases 13 mm. broad; the poste- 

 rior flap projects but a short distance over the anterior border of the 

 next following segment. Genital pores double and opposite in poste 

 rior half of lateral margin. Genital cloaca quite deep. Anlagen of 

 genital canals and female glands visible in the first segments, testicles 

 appear a little later. Male organs: Testicles appear about the thir- 

 tieth segment, between 100 and 150 in number to a proglottid, scat- 

 tered through the median field between the ovaries; cirrus-pouch, 0.5 

 mm. long by 0.17 mm. broad, very muscular, with vesicula seminalis in 

 proximal portion and coiled smooth penis in distal portion. Female 

 organs: Female glands nearly 1 mm. from the lateral border of the 

 segment, some distance from the longitudinal canals; ovarian tubules 

 appear about the thirty-fifth segment, reach their highest development 

 from the forty-seventh to fifty-seventh segments and then rapidly atro- 

 phy, disappearing almost entirely by the sixtieth segment; vagina 

 ventral of the cirrus-pouch on both sides of the segment; uterus single, 

 transverse, proximal to testicles, and possesses proximal and distal 

 blind pouches, similar to those of Cittotcenia pectinata. Ova, 48 to 00 // ; 

 bulb of pyriform body, 23 //. Excretory system : Dorsal canal between 

 ventral canal and nerve. Longitudinal nerves rather close to lateral 

 margin, near distal end of cirrus-pouch. Genital canals cross the 

 longitudinal canals and nerve dorsally. 



Host. Marmot (Arctomys marmota) by Frolich and Blanchard. 



Types. Original type (?). Typical specimens with R. Blanchard 

 (Paris), collection Bureau of Animal Industry (No. 1370, B.A.I.), and 

 collection of Stiles (U.S.N.M.). 



Geographical distribution. (!) Frolich; France (Brianon), by Blan- 

 chard. 



CITTOT^ENIA DENTICULATA (Rudolphi, 1804), Stiles & Hassall, 1896. 

 (Plate XII, figs. 3-8; Plate XIII, figs. 1-3.) 



1804, Tcenia denticulata, RUDOLPHI, Bemerkungen a. d. Gebiete d. Naturg., etc., p. 81. 



1828, Alyselminthus denticulatus (RUDOLPHI, 1802), DE BLAINVILLE, Diet. d. Sci. nat., 

 LVII, p. 607. 



1853, Tcenia goezei, BAIRD, Cat. Entozoa Coll. British Museum, p. 78. 



1881, Cittotcenia latissima, Reihm, Zeitschr, f. d. ges. Naturw., 3 ser., VI, p. 200. 



1881, Dipylidium latissimum (Riehm, 1881), RIEHM, Zeitschr. f. d. ges. Naturwiss., 3 ser., 

 VI, pp. 583-590, pi. v, figs. 5, 15, 17; vi, fig. 2. 



1887, Tcenia latissima (RIEHM, 1881), NEUMANN, Trait6 des maladies parasitaires non- 

 mi crobiennes, p. 426. 



1891, Moniezia denticula \ta] (RUDOLPHI, 1804), R. BLANCHARD, Me"m. Soc. zool. France, 

 IV, p. 187. 



1891, Moniezia latissima (RIEHM, 1881), R. BLANCHARD, Me"m. Soc. zool. France, IV, 

 pp. 187, 451. 



1891, Moniezia goezei (BAIRD, 1853), R. BLANCHARD, M6m. Soc. zool. France, IV, pp. 

 444, 452-457, figs. 21-25. 



