DESCRIPTIONS OF EARTHWORMS. 253 



is no trace of a clitellum visible, as in the specimen des- 

 cribed before. Each ring is marked in its middle by a 

 transverse groove. My statement, that the cephalic lobe 

 should extend over two segments, could not be confirmed. 

 The first dorsal pore was observed between the 14th and 

 15th segment, one ring more backward as I found it in 

 the first individual. 



As for the appearance of the penial setae, situated next 

 to the male genital pores in the angles of the depressed 

 area on segment 17 and 19 (fig. 2), I may refer to my 

 foregoing paper and to the figures 3 and 4. The female 

 genital openings could not be detected. 



In dissecting the worm I found the whole internal side 

 of the body- wall to present a feltered appearance, like in 

 Perichaeta , due to the presence of innumerable faint tubes, 

 which , as already stated in my first paper, highly magnified 

 have a strong resemblance with real segmental organs, 

 though I have not been able to detect neither their ex- 

 ternal, nor their internal opening. On the contrary in Ac. 

 ungulatus the nephridia are very obvious, as already stated 

 by Beddard , and consist of a closely packed rosette of 

 glandular tubes, communicating with the exterior by a 

 large, thin-walled duct; they resemble much the nephri- 

 dia of Microchaeta Rappi Bedd. ^), but I tried in vain to 

 find the internal funnel. 



The vascular system of Ac. Scldegelii agrees much in 

 its arrangement with that of Ac. ungulatus ^). The dorsal 

 vessel is a single tube, communicating with the ventral 

 trunk by five large transverse hearts , situated in segment 

 10 — 13. The number of the pairs of these commissural 

 vessels and that of the septa , separating them from each 

 other, does not exactly correspond to that of the segments ; 



1) Beddard, On the anatomy and system, position of a gigantic earthworm 

 from the Cape Colony; Transact. Zool. Society, Vol. XII, 1886, p. 64. 

 — Benham, Studies on earthworms. Part II, Quart. Journal of Microsc. Science, 

 Vol. XXVI, 1886, pi. XVI, fig. 21. 



2) Proc. Zool. Society, 1886, pi. XIX, fig, 7. 



Notes from tlie Leyden AXuseum , "Vol. IX. 



