OCR Text |
Show 680 MR. F. E. BEDDARD ON NEW [Dec. 20, I name the species 6. Acanthodrilus aquarum-dulcium, n. sp. I need not trouble to give a detailed description of this species, but will merely indicate the differences which it shows from A. falclandicus. It is in the first place a much smaller species ; the measurements of a full-sized specimen are as follows:-Length 47 m m . ; breadth 3 m m . ; number of segments 90. The species is altogether of a more slender build than A. falclandicus and has thinner body-wall. The two atrial pores of each side are connected by a groove in which lies the pore of the sperm-duct; this latter pore, as in A. falclandicus, is just outside the ventral setae which are present upon the xviiith segment, though of course absent or perhaps rather replaced by the penial setae on segments xvii. and xix. Between the ventral setae ou the xviiith and on the xxth segments are a pair of small papillae. I did not find any papillae in the neighbourhood of the spermatothecal orifices. The internal anatomy hardly differs from that of A. falclandicus ; there are, however, no thickened septa; the sperm-sacs may be different, but I was not able to make out their arrangement accurately. I observed egg-sacs in segment xiv. The principal difference between this species and A. falclandicus concerns the penial setae. In the present species they have only a very faint ornamentation at some little distance from the free extremity. The large tubercles characteristic of A. falclandicus are entirely absent; there are merely a series of minute spines with their apices directed downwards. 7. Benhamia whytei, n. sp. Among a large quantity of insects and other invertebrates collected, for Mr. H. H. Johnston, C.B., by Mr. Alexander Whyte, F.Z.S., in Nyassaland was a single example of an Earthworm evidently belonging to the genus Benhamia, which I cannot identify with any of the African forms described by Michaelsen. The specimen was unfortunately not in a sufficiently good state of preservation to admit of an exhaustive account of its structure; but I have been able to ascertain some of the principal characters which serve to discriminate it from the other African species of the genus. The specimen is 2| inches long and is of a dark brown colour. The prostomium is not prolonged over the buccal segment; the dorsal pores commence very early between segments iii./iv. The clitellum occupies segments xiii.-xix.; on the ventral side the male pores are surrounded by a circumscribed area, as in other species of the genus; within this area there is no development of glandular tissue. The apertures of the atria are as usual upon segments xvii., xix.; the orifices are circular and each is surrounded by a circular rim ; the two apertures of each side are connected by a groove; the ventral setae of the three segments xvii., xviii., xix. are absent. Their place is taken on the xviith and the xixth segments by the penial setae. |