[35] OLIGOCHiETOLOGICAL RESEAEOfiES. 913 



Claparede, in his celebrated aud excelleut work ''■ Rechcrches Anatom- 

 iques sur les OligocMte^," describes three species of vvorais belougiug- to 

 the family of TuUficidce. Of these, two species are named Lmnodrilus, 

 a genus here for the first time introduced, aud one classified in tlie old 

 genus Tubifex. Tuhifex Bonneti, as being the best kuown species in the 

 genus, can evidently serve as type for the same. This species is also the 

 best described and figured of the three, and for this reason I believe that 

 Olapar^de studied the same last of all. 



If we turn to the above-mentioned work (PI. II, Figs. 1, 3, and 4), we 

 find here not less than three different delineations of the copulative or- 

 gans proper, and as far as I can judge his drawings of this species cor- 

 respond more with my general description of the copulative organs than 

 with his own. In the above Fig. 4, c is evidently the lumen of the penis ; 

 /the lower end of the penis sheath, the u^jper end of which is not seen; 

 I is the lower or exterior orifice of the iQterior oviduct, the upper end 

 or interior orifice of which is plainly drawn, but not marked with any 

 letter of reference. Between g and b is seen a circular line, which I be- 

 lieve must indicate the exterior orifice of the exterior oviduct. The 

 upper end of this oviduct is not seen in the drawing. In Fig. 1, which 

 represents the same organ, we find the interior orifice of both oviducts, 

 the exterior one being represented as seen in optic section. What I 

 here have designated as the exterior oviduct is by Claparede represented 

 as being a cloaca, and is in all the figures delineated as being continuous 

 with two longitudinal trunks of muscles outside the same. That they, 

 however, are entirely separated from the former is quite certain, and I 

 have also figured them as such whenever they have been present, which, 

 however, has not been the case in every species. According to Fig. 3 

 the exterior coating of the atrium e ends somewhere near b\ and does 

 not inclose the oviducts. This is also in conformity with my own ob- 

 servations of the development of the oviduct and penis (see Figs. 17 and 

 18.) 



If this is the case, and (in Claparede figures) if e does not inclose the 

 oviduct m, b, and g, why could not the true interior aperture be found 

 at 6^, and the ova enter through the same ? The aperture at t' is evi- 

 dently there for some purpose, and it is most reasonable to consider it 

 the aperture of the oviduct. But, according to Claparede, the interior 

 aperture should be looked for much ^higher up, near the upi>er end of 

 the atrium, just at its junction with the efferent tube proper. A more 

 inconvenient aud difiicult entrance for the ova could hardly be found, 

 it not only being very small, but, worst of all, is covered by the pros- 

 tate glands. It is true that the exterior layer of the atrium ends at 

 the base of the efferent duct proper, but I have not been able to see any 

 aperture here, and cannot imagine which power or which muscles should 

 convey the ova towards the genital porus. Further on I will explain 

 why the exterior coating of the atrium ends here and is not con- 

 tinued round the efferent duct. 

 H. Mis. 67 58 



