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Show 1901.] ANNELID OF THE GENUS ALMA. 219 miles away from the locality which produced A. millsoni, there is & prima facie possibility of its being distinct from that form. The general aspect is illustrated in the accompanying figure (text-fig. 59, A ) , and is like that of other species of Alma. The " penial processes" are not especially long, measuring as they do about 10 m m . as against a total body-length of 125 m m . These measurements are in all probability fairly accurate ; for, though the worms were not in a very excellent state of preservation, they were, as it appeared to me, not unduly softened and presented no appearances of having been pulled out iu the course of preparation or of subsequent handling. The square shape of the body both in front of the clitellum and posteriorly was quite well shown, a condition so characteristic of this genus, as of some others (e. g. Allurus, Gly-phidrilus) which are at least sometimes aquatic in habit. To the corners of the quadrangular contour corresponded the pairs of setae which in the present worm are not closely applied to each other. Throughout the body each seta is at some little distance from its fellow of the couple; and this arrangement persists unaltered to the end of the body, which is the case in A. millsoni, but not in any other of the remaining three species of the genus. In A. millsoni, however, the setae are ornamented at the tip. In the present species I did detect a faint trace of ornamentation of the same nature as that of A. millsoni, where are denticulate ridges covering the free end of the setae. The red colour of the setae which I have referred to in A. millsoni was apparent at the imbedded end of the seta, where it is thick and squarely cut off. This end was quite red in several setae which I noted, the red coloration was not always thus obvious. The penial appendages of the present species differ at least from those of A. millsoni with which I have been able to compare them. They are more like those of A. stuhlmanni. In contrast to those of A. millsoni, the penes (as they may be termed in the absence of precise knowledge as to their functions and since they bear the male orifice) of the present species are not flattened and riband-like organs, but plumper aud deeply excavated on the ventral surface; so deep is the excavation that the process, when viewed from below, is quite boat-like in shape. At the free extremity of the organ the depth is much greater than elsewhere; the part of the penis attached to the body (text-fig. 60), and for a little distance away from this as far as just before the first sucker, is not excavated, but quite flat though still fairly thick. This seems to show that the hollowing out of the organ is not a matter of unequal contraction, but is a real difference serving to differentiate the species at least from A. millsoni. Nothing of the kind is to be seen in Michaelsen's figures of A. stuhlmanni and of A. emini; but Levinsen figures the penes of A. nilotica as something like those of the present species. The attachment of the penes to the body-wall appears to present features of difference which may serve to assist in the discrimination of the species. In A. millsoni, as I have been able to assure myself by a re-examination of several |