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Show 1900.] ON A NEW SPECIES OF EARTHWORM. 653 5. On the Structure of a new Species of Earthworm of the genus Benhamia. By FRANK E. BEDDARD, M.A., F.R.S., &c. [Received May 9, 1900.] Two specimens of a species of Benhamia have been kindly placed in m y hands by M r . Budgett, of Trinity College, Cambridge. They were collected by him on McCarthy Island on the Gambia, and prove to be in an excellent state of preservation for anatomical purposes. I believe them to be referable to a new species, of which 1 propose to associate the name with that of M r . Budgett. The following is a description of Benhamia budgetti:- External characters. The length of one individual (the two were fairly equal in size) was 116 mm., by 5 or 6 m m . in breadth. The buccal lobe cannot be described with accuracy as it was almost entirely withdrawn into the buccal cavity. In correspondence perhaps with this withdrawal, the first segment of the body was deeply grooved dorsally and before backwards. The setae, as usual, are closely paired. All the four pairs are about equidistaut, and the area occupied by them collectively is about 3 of the circumference of the body. They do not appear to be wanting upon any of the segments of the clitellum except the ventral pair upon the xviith and xixth segments, where they are of course replaced by the penial setae, and, I think, the corresponding pair upon the xviiith segment. These setae are generally, but not always, absent in Benhamia. The clitellum occupies entirely segments xiv.-xx. inclusive, and also, at least in one specimen, the latter half of segment xiii. It is incomplete along a narrow ventral line which corresponds to the area occupied by the ventral pairs of setae and their interspace. This area forms almost a gutter owing to the bulging of the integument along each side, which how7ever does not commence until the xvth segment. Dorsal pores are present, and are especially conspicuous at the tail end of the body. The genital papillce of this species are not numerous. There are a pair upon segment xx. which extend on to xix., and are in line with the orifices of the spermiducal glands. A median papilla lies upon the end of segment xx., whose area is rather less than that of the two anterior papillae and tbeir interspace. This papilla was only obvious in oue specimen. Finally there is a larger median papilla upon the twenty-second segment, whose area extends beyond the ventral setae. It is bardly to be separated from the papilla in front. These papillae are all conspicuous from their white colour. P R O C . Z O O L . Soc-1900, N o . XLIII. 43 |