4 Art. 3. — T. Kabiiraki : 



merges behind into the tmnk, being marked off by a gentle neck- 

 like narrowing. The trunk gradually widens backwards to the 

 region of copulatory organs, and then begins to taper to the pos- 

 terior body-end which is somewhat rounded or bluntly pointed. 



Size. — The large specimens are about 4 mm. in length, when 

 alive and fully extended, and 1 mm. across in the widest part of 

 the body. 



Colour. — The translucent body is generally of a whitish or 

 light brownish colour, but may present sometimes various sorts of 

 hues — not infrequently smutty yellowish l;)rown, yellow, orange, 

 red, gray or green — according to the \arying colouration of intes- 

 tinal contents. The darkish pigments are well developed along 

 the head-margin and most densely in the region of the eyes, 

 bringing about a central clear space. The pharynx and the copu- 

 latory organs may fairly well appear as clear spaces. The ventral 

 surface is of much lighter colour than the dorsal. 



Eyes. — The two crescentic eyes are fairly closely approximat- 

 ed, but far removed behind the anterior end of the body, the 

 distance being much larger than that of either eye from the lateral 

 neck-margin of the same side, and the latter being a little longer 

 than double the distance which intervenes between them ; each 

 eye is surrounded by a small, oval, non-pigmented area. 



Digestive Organs. — The mouth is situated at about the hind 

 end of the middle third of the body. The insertion of pharynx 

 takes place at a short distance behind the middle of the body. 

 The anterior gut trunk is provided with 7-9 pairs of lateral 

 branches, while the posterior trunks give off each about 10 

 branches on both sides, those of inner sides being very short. 



Genital Organs. — The genital aperture lies nearly half-way 

 between the mouth and the posterior body-end, and leads directly 

 into the simple atrium. Numerous small testes, ventral in posi- 

 tion, are arranged on both sides of lateral nerve-cords from close 

 behind the ovaries to tlie pharjaix -insertion, but farther behind 

 only on the outer side of the same, ceasing altogether to exist at 

 about the level of the mouth. The vasa deferentia fuse together 

 in the penis bulb to form a short common duct which soon opens 



