44 PKOCEEDINGS OF THE NATIONAL MUSEUM vol.70 



measured 0.135 mm. in length, 0.015 in diameter at base, 0.018 at 

 the bulbous enlargement and at the tip, and was 2.5 mm. back of 

 the scolex. The cirrus-pouch is long, slender, cylindrical, at first 

 reaching to or beyond the median line; later it may become some- 

 what curved, or spiral; its walls are thick, and appear to be made 

 up of longitudinal muscles. Its inner portion functions as an outer 

 seminal vesicle. An inner seminal vesicle was seen near the median 

 end of the cirrus-pouch, and connected with it by a short vas 

 deferens. In some of the younger proglottides this inner seminal 

 vesicle was relatively large. Thus the diameter of an inner seminal 

 vesicle was 0.054 mm., the diameter of the adjacent cirrus-pouch 

 being 0.042. Only male genitalia appear in the anterior part of 

 the strobile. The three testes are small with circular outlines and 

 placed near together nearly in a straight line, the one nearest the 

 antiporal margin of the proglottis being a little in advance of its 

 neighbor. This observation was made on a proglottis 0.03 mm. in 

 length and 0.24 in breadth; the diameter of a testis was 0.024. The 

 vagina lies along the ventro-posterior border of the cirrus-pouch ; a 

 seminal receptacle was faintly shown near the median line. The 

 ovary was not clearly shown in the mounted specimens. It appears 

 to be small and rather compact, but where best seen somewhat 

 unsymmetrical with reference to the median line, and more or less 

 lobed (fig. 146). The vitelline gland was compact and not lobed. 

 The uterus, beginning as a small tube on the ventral side of the 

 ovary, develops rapidly in succeeding segments, and ultimately 

 occupies practically all of the medullary space. In ripe portions of 

 some strobiles the septa between the proglottides are indistinct, so 

 that the relatively large ova appear to be continuous from one pro- 

 glottis to another. Diameter of onchosphere 0.030 to 0.036 mm., 

 length of embryonic hooks 0.012. Dimensions, life: Length 10: 

 diameter of scolex 0.32, length 0.32; diameter of sucker 0.14; length 

 of exserted rostellum 0.20, diameter at base 0.08, middle 0.03, tip 

 0.08; breadth of neck 0.20; distance to first segment 0.080, length of 

 first segment 0;02, breadth 0.22 ; length of last segment 0.24, breadth 

 0.30. Length of longest strobile m.ounted in balsam 24 mm. Dimen- 

 sions of mounted specimens: (1) Length 9; breadth of scolex 0.24, 

 length 0.16; breadth of sucker 0.10, length 0.12; length of rostellum 

 0.18; length of sheath 0.18; length of posterior segment 0.14, breadth 

 0.24. (2) Length 24; breadth of scolex 0.19; breadth of sucker 0.11 ; 

 length of posterior segment 0.14, breadth 0.49. Further details a^'e 

 given under records of collections. 



The foregoing account is based on material from Marila viaHla, 

 new host. Following are notes on material from the other hosts in 

 which this species was found : 



