184 Memoirs of the Indian Museum. [Vol. I, 



MEGASCOLEX HENDERSONI, MICHI.SN. 



(Plate xiii, figs. 22, 23.) 

 M. h., MICHAELSEN, in Mt. Mus. Hamburg, xxiv, 162, f. 10. 

 Present four mature specimens. 



External Characters.— The dimensions of the specimens differ somewhat. 

 The smallest is 140 mm. long, and 5 — 6 mm. thick, and is composed of no seg- 

 ments. The largest is 230 mm. long, 7 — 8 mm. thick and composed of 152 segments. 



Colour dorsally, at the anterior part of the body with the exception of the 

 first segment, bluish grey, sometimes distinctly iridescent, passing into a brownish 

 or reddish grey backwards; yellowish grey ventrally. 



Head tanylobous, the sharply marked lateral borders of the rather broad hinder 

 appendix of the prostomium converging somewhat backwards. The intersegmental 

 furrow 1-2 is distinct only dorsally, ventrally it is nearly extinct. Each segment of 

 the anterior part of the body, with the exception of the first, is distinctly annulated 

 by two ringlet-furrows. The middle ringlet, which bears the setae, is very prominent, 

 like a rounded wall. 



The setse, indistinct (missing ?) on the 2nd segment, are in general moderately 

 large, somewhat larger on the anterior part of the body than elsewhere. They are of 

 the usual S-shape, but highly ornamented and provided with irregular toothed trans- 

 verse ridges; the distal end has an obliquely twice-ridged tip. The circles of setse 

 are regularly but not broadly interrupted ventrally {aa = J.\--2ah), irregularly and not 

 broadly interrupted dorsally {zz =i—2yz). There is no marked difference between the 

 density of the circles ventrally and dorsally, but dorsally they are somewhat irregular. 

 Numbers of setse : 28-v, 33-viii, 38-xii, 36-xx, 40-xxvi. 



First dorsal pore at the intersegmental furrow 5-6. 



Glitellum saddle-shaped, leaving free the ventral side, occupying segments 

 13 — 19 ( =7), but at the 13th and 19th segments not quite as distinctly marked as at 

 the intermediate segments. The clitellum is not prominent and is distinguished only 

 by its darker colour and by the absence of a middle wall-shaped annulet, bearing 

 the setse, — the segments being divided by only a single ringlet-furrow into two annulets, 

 the hinder one bearing the setse. 



Male pores (fig. 22) at the i8th segment in the lines of setse b somewhat behind 

 the zone of setse, each on a small, nearly circular papilla. The male pores are distant 

 one from the other about one- tenth of the circumference of the body ( o' cf =ca. 



Female pores indistinct (on the 14th segment in front of the setse a ?). 



Spermathecal pores one pair in the intersegmental furrow 8-9, opposite the 

 interspace between the setae b and c, distant one from the other about one-eighth 

 of the circumference of the body ( / / =ca. |-m). 



. Copulatory organs (fig. 22), in an apparently constant arrangement: 

 three pairs of rather small transversely oval papillse at the hinder border of seg- 



