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Show 1903.] NEW SPECIES OF EARTHWORMS. 213 descending limb of the oviducal loop, which constitutes the " Eitrichterblase " of Michaelsen. No communication between this short diverticulum of the oviduct and the general ccelomic cavity could be detected. Evidently, however, it is the forerunner of the funnel which opens into the fully developed receptaculum, or, possibly, of both. It is noteworthy that the oviduct is divisible into two regions. The section lying nearest to the spermathecal sac is of a wider calibre than that lying nearer to the external orifice. Furthermore, the lumen of this wider section is a straight tube, while the lumen of the narrower section of the oviduct is sinuous in its course within the muscular sheath. It is possible that the wide straight section is really to be looked upon as a greatly drawn-out funnel, drawn out by reason of the growth of the spermathecal sac. The walls of the oviduct, as is the case with other Eudrilidae, are very stout and muscular; and attention has already been called to the fact that part of the oviducal tube runs a sinuous course, independent, therefore, of its muscular covering. These facts, coupled with the conditions obtaining in Eudrilus \ where the oviduct runs for a considerable space actually within the septum, lead me to consider that the muscular wall of the oviduct in Stuhlmannia may be a purely adventitious sheath, not belonging to the oviduct at all, but consisting chiefly of the otherwise missing septum between segments xiii./xiv. Its continuity with the receptaculum can at any rate be explained on this view, which is in any case not at variance with the other facts to which I have just called attention. The present species, in correlation, it is to be presumed, with the entire absence of a penial process, does not possess the median unpaired bursa propulsoria which characterizes S. variabilis. In the former point possibly, but not certainly, it agrees with S. gracilis. Dr. Michaelsen states, only as a possibility, since he only examined two specimens, the absence of a copulatory process in S. gracilis; furthermore, a thickening of the integument of segment xv. appeared to him to be possibly intelligible as a not fully developed penis. With regard to the presence or absence of a bursa propulsoria he is silent. Stuhlmannia michaelseni, however, cannot be confused with S. gracilis by reason of the characters of the penial setae. They are provided at the end with a row of sharp denticles on either side as in S. variabilis. In short, I think that a case has been made out for the creation of a new species of this genus Stuhlmannia. Bettonia lagaviensis, n. g. & sp. Of this apparently new genus and species I have examined but a single specimen, complete and sexually mature. It measures 90 mm. by 4-5 mm. in breadth. The colour is bluish violet. It 1 Beddard, " On the Gonad Ducts and Nephridia of E u d r i l u s P. Z. S. 1902, vol. ii. p. 89. |