244 J. H. ASHWORTH. 



Apertures. 



The raoutli is a wide transverse ventral slit between the 

 peristomium and the first cliastigerous segment. It is overhung 

 by the prostomium, and is bordered anteriorly and poste- 

 riorly by papillae (fig, 2). The pharynx, when fully pro- 

 truded, is smooth and globular. 



The anus is terminal, and surrounded by four slender 

 anal cirri, two on each side, situated somewhat ventro- 

 laterally (fig. 6). In one specimen there are five cirri, there 

 being three on one side and two on the other, but this is 

 evidently abnormal. In full-grown specimens the cirri are 

 are about "8 to 1*0 mm. long, and "05 to "06 mm. thick. 

 There is a small protuberance on each side of the mid-ventral 

 line of the pygidium, from which the two cirri arise. 



The nephridiopores are exceedingly minute and diffi- 

 cult to see. The first nephridium opens on the fourth 

 chsetigerous annulus, but as this nephridium is very small its 

 opening can usually be found only in sections. The second 

 nephridium is a little larger, but its opening is almost equally 

 difficult to find. The apertures of the succeeding nephridia, 

 while being small, are however visible in cleared preparations, 

 and occasionally in surface view of favourable spirit prepara- 

 tions. Each nephridiopore is a minute oval aperture, situated 

 ventral and anterior to the neuropodium of the segment on 

 whicli it opens (fig. 5). The aperture is close to the anterior 

 border of the chastigerous annulus, and it is often obscured 

 by lying in the gi'oove which separates this annulus from 

 the pi'eceding one. In the most favourable specimens in my 

 possession the largest nephridiopores are only about "06 mm. 

 in diameter. Towards the posterior end of the animal, 

 where the nephridia become smaller, the nephridiopores 

 become correspondingly more difficult to see in surface view, 

 although they may be distinguished in sections in each seg- 

 ment almost to the posterior end of the worm. In a specimen 

 13"6 mm. long the last visible nephridiopore is only 1 mm, 

 from the posterior end of the animal. 



