1920.] J. Stephenson: Oligochaeta from India and E. Persia. 259 



The worm has been described by Rosa from Burma, from a single specimen which 

 was not in very good condition, and not fully mature. As I have had a considerable 

 number of examples, carefully preserved by Mr. Thapar, to whom my thanks are 

 due for these interesting specimens, I give below a fairly complete description. 



External Characters : — Length 120 mm. ; diameter at and in front of the clitellar 

 region 3 mm., behind the clitellum 2 mm. Colour flesh-colour or greyish, no distinct 

 pigmentation ; a slightly darker mid-dorsal stripe. The posterior half of the body is 

 flattened on the dorsal side, and even concave in the hinder third ; the ventral sur- 

 face is flattened or slightly concave for the greater part of its extent. Segments 202 

 in the example which was counted. Segment vi is biannulate, vii is triannular, and 

 so are viii and ix, but these may be further subdivided ; the succeeding segments as 

 far as xv are bi- or triannulate. The anterior end of the body is tapering ; the pos- 

 terior end becomes gradually thinner also. 



The prostomium is large, zygolobous, and triangular. Dorsal pores are absent. 



The setae are paired ; behind the clitellum, the section of the body being some- 

 what quadrangular, the couples are at the four angles ; ab is a little less than half aa, 

 is equal to half be, and is equal to cd ; dd is a little but not much greater than aa. 

 The setae become very small in front of the clitellum, and also wider apart. In the 

 posterior part of the body the setae are still at the angles, but the intervals are rather 

 different; dd becomes larger and be smaller ; ab = \aa = half be = cd = *dd. 



Under close examination the anterior segments showed rings of minute pits ; 

 these were on the middle annulus where the segments were multiannular ; possibly 

 they represent sense organs. 



The clitellum is rather indefinite in its extent ; beginning at segment xvi it ex- 

 tends back to xxvi-xxxiv. The wing-like ridges extend ventro-laterally along each 

 side from segment xviii to xxiii, xxiv, xxv, or the anterior part of xxvi ; they arise 

 from the body-wall outside the line of the ventral setal couples. 



The characteristic papillae are large, round, flattened or slightly depressed in the 

 middle, and situated on the posterior parts of the segments. They are lateral or 

 median ; the former series occur in line with or slightly dorsal to the attachment of 

 the winglike folds of the body-wall, are usually paired, and may be found on any 

 of the segments x-xvii, as well as occasionally on xxiii, xxv, or xxvi; they are com- 

 monest on xiii-xvii, especially xv-xvii. The median papillae are not so common as 

 the lateral ; I have found them only on xi-xv, and xvii and xviii. Median papillae 

 may be absent altogether ; the lateral papillae may be as few as two pairs, or two on 

 one side and one only on the other. 



Internal Anatomy :• — The first definite septum is 45, which is thin ; 5/6 is slightly, 

 6/7-9/10 moderately, and a few succeeding ones slightly thickened. 



The gizzard is in segments vii and viii ; septum 7/8 is adherent to it at about 

 its middle, but there is no constriction there ; it is rather small, being no wider than 

 the preceding segments, and is fairly soft. The intestine begins in segment xvi. 



Hearts are present in segments x and xi, and, in the specimen dissected, on the 

 right side in ix also. 



