iQr4.] "^ J.Stephenson: Oligochaeta. 399 



was a batch of three specimens with a fragment of a fourth, 

 taken at Upper Rotung, alt ca. 1000 ft., 11-1-1912. 



Pheretima hctcrochaeta (Mchlsn.). 



Kobo, Abor country, alt. 400 ft., in rotten wood; 30-xi-igil and 

 S-xii-igii. Two specimens, in a tube \\'\i\\ Pei'io)iy.x koboensis a.nd 

 Perionyx kenipi . 



Sadij'a, N. E. Assam, under logs; 25-xi-i9ii. A single specimen, in 

 a tube with Perionyx excavatiis. 



This species appears to be variable. In one of the two 

 specimens from Kobo the typical characters and arrangement 

 of the setae were easily recognizable ; in the other these were 

 by no means evident, and all that could be said was that the 

 ventral setae of segments iii-viii were enlarged and rather irregu- 

 larly arranged. In this second specimen the setae of segments 

 X and xi were much smaller than those of neighbouring seg- 

 ments ; in the first the setae of x were perhaps rather smaller 

 than those of ix, but not smaller than those of the following seg- 

 ments. In the Sadiya specimen, the arrangement of the setae 

 on the ventral surface of the preclitellial segments was very 

 irregular, — due possibly in some cases to setae having fallen 

 out; where they were sufficiently regular to permit of descrip- 

 tion^ the arrangement approximated to that of typical specimens. 



In the Sadiya specimen, the clitellum encroached slightly 

 on segments xiii and xvii (=3^). Genital papillae, small, 

 nearer together than the spermathecal apertures, and situated 

 about midway between the setal ring and the anterior limiting 

 groove of the segment, were found on segment viii in one of 

 the specimens from Kobo, on vii and viii in the other, and on vii, 

 viii and ix in the specimen from Sadiya. 



Prostates were entirely absent in the specimen from Kobo 

 which I dissected, and in the one from Sadiya; the terminal 

 part of the duct was strongly curved in the shape of the letter S. 



As further variations from the condition described by 

 Michaelsen (2) may be mentioned the beginning of the dorsal 

 pores from furrow [2, their absence on the clitellum in the 

 Kobo specimens (but not in the other), and the origin of the 

 intestinal caeca in segment xxvii. 



Pheretima lignicola, sp. nov. 

 (PI. xxvii, fig. 17.) 



A single specimen, in a tube with Perionyx excavatiis. In rotten 

 wood; Dibrugarh, N.E. Assam ; 20-xi-igii. 



Length 4I inches; breadth 4-5 mm.; colour olive-green, 

 slightly darker dorsally in the anterior region. Segments 90. Body 

 tense, as if distended ; intersegmental furrows absent as grooves 

 behind the clitellum, present in front of clitellum. Setae implanted 

 on circular ridges, especially prominent in front of clitellum ; 

 no other secondary annulation. 



