430 Dr. W. B. Benham on some 



the absence of such a brief risumS in many instances whilst 

 reading through the literature of the genus. 



PericJiCBta jampeana, sp. n. (PI. XX. fig. 1.) 



Three specimens are included in this species. 



The colour is a nearly uniform dark olive-green on the 

 back ; the chgetal bands, so usually present in the genus, are 

 here no lighter than the ground-colour. The worm is not per- 

 ceptibly darker anteriorly. The dark colour extends well round 

 on to the ventral surface, leaving a light stripe with a pinkish 

 tint running along the middle third of the ventral surface ; 

 measured on the dissected specimen this stripe is 7 millim. 

 broad, the circumference of the worm being 36 millim. But 

 the anterior end of the body for about the first twenty-six 

 segments does not present this light ventral band ; here the 

 dark greenish tint extends right round the body, over a very 

 unusual number of segments, and the ventral surface is scarcely 

 lighter than the back. One specimen was " mottled " on the 

 upper surface with pinkish patches, some large, others small, 

 irregular and varied in shape. 



The clitellum is nearly black, though with a bluish tint. 



The worm is, except in front of the clitellum, of about the 

 same diameter throughout; the posterior end is very suddenly 

 rounded, so as to appear almost truncate. 



Twoof the specimens measure 315 X 1 2 and 310 X 10 millim. 

 respectively, and the former consists of 150 segments. 



The clitellum, which occupies the normal three segments, 

 is not swollen, presents a trace of the intersegmental grooves, 

 but no chgetee. 



The male pores are conspicuous as wide depressions in a 

 pinkish circular area ; the eighteenth segment has a pink 

 dumb-bell-shaped area, with a slight papilla at each end ; in 

 this papilla is the pore itself : the outer lip is rounded and 

 prominent, but not sharply marked ; the inner lip scarcely 

 exists, as the surface slopes down gradually to the pore. 



Between the two pores are 13 or 14 chsetsB (fig. la). 



It may be mentioned that the distance between the pores, 

 as measured by compasses the points of which were placed in 

 the pores, is 5, 6, and 8 millim. respectively, the last in a very 

 soft specimen. 



The spermathecal pores are between segments vii./viii., 

 viii./ix., each in a small pinkish area; about 19 or 20 chaetse 

 between pores. 



There are no copulatory papillse. 



