20 Art. 9.— M. Yeri and T. Kaburaki : 



punctate pigments present all over in reticular distribution, leaving 

 numerous small mesh-spaces free of them. The pigments are most 

 densely developed over the pharynx and the genital end-organs« 

 Gut branches may be discerned on the dorsal side in a pale 

 brownish colour. In mature specimens, there are visible behind 

 the pharynx, two ill-defined streaks of a reddish colour, converging 

 posteriorly and marking the position of uteri. The ventral surface 

 is of a much paler colour than the dorsal, without blackish pig- 

 ments. The much folded pharynx, the seminal canals, the 

 muscular vagina bulbosa and the radiating shell glands can be seen 

 with more or less distinctness in a whitish colour on that side. 



Dorsal tentacles slenderly conical, dark- coloured, situated at 

 about the hind border of the first quarter of body. Normally they 

 occur in a single pair; but, as the individuals grow old and large, 

 there may take place adventitious production of some new dorsal 

 tentacles close to the normal; so that, in large examples there may 

 exist, on both sides or on one side only, a group of more than one 

 tentacles arranged apparently without definite order. In a case 

 which came under observation there existed on the left a group of 

 four tentacles and on the right another of seven. 



20 Tentacular eye-spots in a close ring 



at base of each tentacle. Cerebral eye- 

 spots irregularly scattered and scarcely 

 separable into distinct groups. 



Mouth subcentral, opening into the 

 much folded pharynx. Main gut giving 

 rise to six pairs of intestinal branches. 

 Textfig. 20. Eye-spots of Pianocera Testes distributed in ventral parts 



reticulata. . ' y L 



m the body. Seminal canals (textfig. 

 21, sc) are much convoluted tubes, which, beginning at about the 

 level of the female genital aperture, extend anteriorly on either 

 side, taking a course nearly parallel to the median line up to about 

 the level of the anterior end of the cirrus bulb. There they bend 

 mediad, finally to join the seminal vesicle (textfig. 22, sv) 

 which is situated immediately behind the pharyngeal sac and 

 ventrally to the hind end of prostate. Posteriorly the seminal 



