■[QQ S. OOTO. 



trical. Anterior sucker without any septum. With only a single pair of 

 stichj glands near the anterior end of the body. Common genital opening 

 just behind the posterior end of the oesophagus ; atrial spines straight 

 and conical, about 0.016 mm. in length, composed of two parts, the 

 basal, hemispherical portion and the distal, spinous portion mounted 

 on the former. Ocary slender, situated at about the middle of 

 the whole length of the body; roughly speaking, S-shapad, and 

 making numerous minor windings, especially in its anterior half. 

 Vagiiuil opening single, median, and dorsal, armed with low conical 

 teeth, and situated at a short distance behind the common genital 

 opening. The single vaginal canal divides into two at a point 

 which is as far behind the external opening of the vagina as this is 

 behind the genital opening; and the two vaginal canals after proceeding 

 backwards for a short distance, become continuous with the paired 

 yolk-ducts at the point marked with an * in fig. 5, PI. I. The paired, 

 ijolk-ducts unite at about the anterior end of the ootyp, and the single 

 yolk-duct opens into the oviduct just where this is continued into the 

 ootyp. The genito-intestinal canal opens into the oviduct about twice 

 as far from the origin of the latter as from the beginning of the ootyp. 

 The vitellaria of the two sides are distinct in front ; the lobes are 

 small and scattered, and are situated mainly on the dorsal side of the 

 intestine. Testes occupying a little less than one-half the whole median 

 portion of that part of the body which lies behind the posterior 

 end of the ovary; of small size and very numerous. The terminal 

 portion of the vas deferens (PI. V, fig. 6) is armed with conical spines 

 just like those of the genital atrium. The branches of the intes- 

 tine form a complicated net-work (PI. Ill, fig. 2). Caudal disc con- 

 tinuous with the rest of the body. Posterior suclcers occupying somewhat 

 more than one-third the entire length of the body; moi'e numerous 

 and smaller in size on the right than on the left side, there being about 



