Olijoclivta of Travancore. 503 



Tlie posterior third of the body is coiled and distinctly 

 fetragonous ; the transverse section of the tail is trapezoid, 

 tlie largest side corresponding to the dorsal surface of the 

 body, and the four angles to the bundles of the setae. 



The tail is smaller than the cephalic region. The anal 

 pore appears as a short longitudinal cleft in the middle 

 dorsal line of the last three segments. 



Colour violet-grey, clearer and with a tendency to rose-colour 

 at the clitellum, especially on segments .... xvii.-xxxiii 



The body-wall is very thin, especially at the tail, and 

 internal organs can be seen through them : for example, the 

 spermathecse on intersegmental furrows xiii.-xiv. to xvi.- 

 xvii. in mature specimens. 



The setse are paired, but not strictly. On x. segment 

 oanearly = 2 ab, ab = ^ he, cd=ab, dd a little larger than 2 cd 

 or than aa. On the posterior half of the body the setai are 

 more strictly paired: aa nearly = 3 ah, aa = hcj ab = cd, dd 

 nearly = 4 cc?. 



All mature specimens are provided with unpaired middle 



ventral papiilte on segments (xii.) xiii. to the xviii 



xxiii. (xxv.). In one specimen there are also small median 

 papillre on segments xxxiii.-xxxv. 



Failed lateral papillce are found close latej'ally to the setse b 

 of segments xviii.-xxvi. and xxxiv.-xxxv. 8ome speci- 

 mens are also provided with scattered paired papillae on 

 segments xvi., xvii., and xxvii.— xxxiii., or on some of these 

 (PI. XIII. tig. 11). 



All the papillse are slightly swollen, more so near the 

 posterior than the anterior margin of their respective seg- 

 ments. Each papilla has the appearance of a little grey 

 round stain, which is provided in its centre with a small 

 whitish circle (PI. XIII. tig. 12). 



The clitellum is developed all round the body, and occupies 

 at most twenty-five segments. Indeed, in a specimen from 

 Achencoil River banks it extends from the xv. to the xxxix. 

 segment, and is more or less evident from its rose-grey 

 colour, and for the slight tumefaction, which is in relation 

 to a greater quantity of glandular cells in the epidermis. 



In other specimens the posterior margin of the clitellum is 

 between the xxxv. and xl. segments, while its anterior margin 

 seems to be constantly on intersegmental furrow xvii.-xviii. 

 All the intersegmental furrows of the clitellum are recog- 

 nizable, but not very distinctly those included between the 

 xxv. and xxxiv. segments (PI. XIII. tig. 11). 



The clitellar region may be depressed, at least partially, 

 and its lateral margins, often rather sharp, are provided with 



