KKPOHT ON TllK t H.K .1 ii If.Kl'A HKXH AM. -00 



Vascular Sy!<tem. — This presents a large heait in segment viii., 

 and in the preceding segments, iv. to vii. paired, very undulating 

 connnissurals, which are also repeated in the subse(]uent segments 

 throughout the body. At the liinder end, these become much 

 longer, and therefore take a more undulating course along the 

 inner surface of the body wall — but they give oft' no branches ; 

 there is no network. 



I made no particular study of the ucplir'ulia^ owing to the 

 broken condition of the sections, due to the sand contained in the 

 intestine. I note, however, that the nephridia couunence behind the 

 clitellum ; here the pores are well defined, and eA'ident in the body 

 wall in an individual that had been bisected and flattened out, 

 after removal of the gut. These pores ai-e in line, as usual, with 

 the ventral chai'tje, but no similar pores occur anteriorly to the 

 clitellum. 



Remarks. — This species belongs to that grou}) of the genus 

 Tubifex, which is chaiucterised by the presence of special copu- 

 latory ch?eta^ near the aperture of the spermatlieca, as in the 

 familiar European species 7\ (FKnruniori/cfes) harbatvs, Grube. 

 The genus Tubifex, as emended by Michaelsen (1900), includes a 

 number of species which have been described under several 

 generic names such as Ilpinit'uhlfe.r, Spiro.y>rni/fi, Ifi'f'-roi-Iidfa, 

 EmbolocejyhahiSj as well as Psanimoi-yrfcs. 



Of the " Psamnioryctes " group only eight species have been 

 recorded, viz.: — T. vehitinnn, Grube, T. bnrbafus, Gr., T. hi'itsrheri, 

 Bretscher, T. camerani, Visart, T. illusfris, Ditlevsen, 7'. /'oxsor, 

 Ditl., T. sarneensis, Pierantoni, and T. hamafus, Moore. 



From each of these the present species differs in certain 

 characters, such as the form and number of the chieta^ in the dorsal 

 bundle, details as to the proportions of the teeth of the ventral 

 chseta?, form of the copulatory clnetie, absence of penial sheath, 

 etc., etc. 



The species which it most closely resembles is T. In'usi-ltrri 

 (with which T. camerani is possibly identical), but from this the 

 form of the copulatory clneta seems to mark it oft". In that species 

 the free end is sharply curved and pointed, it is twice the length 

 of the ordinary ventral chfeta, and thicker than it : it is also said 

 to be grooved on its exposefl surface. It is possible that in my 

 specimens of T. chn-irHs, the copulatory cha?ta is not fully formed — 

 see above as to the difficulty of studying it — and that when fully 

 formed it would differ from the condition described above, but I 

 do not suppose that this is the case, and I believe that we are 

 justified in regarding it as distinct from the European forms. 



