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Show 1900.] ON THE EARTHWORMS OF THE " SKEAT EXPEDITION." 891 5. On the Earthworms collected during the (i Skeat Expedition " to the Malay Peninsula, 1899-1900. By FRANK E. BEDDARD, M.A., F.R.S. [Eeceived November 20, 1900.] The Earthworms upon which I now report were collected by Mr. R. Evans of Oxford, during the Skeat Expedition in the Malay Peninsula. They belong for the most part to the characteristic and abundant Oriental genus Amgntas. The collection contains, however, a number of examples of the ubiquitous Pontoscolex corethrura and of a small Benhamia. Since so many species of Amyntas are now k n o w n - I allow 109 or so in m y recently published l revision of the genus-I was not prepared for the large number of novelties that occur in the collection. It must be remembered, however, that this region of Asia has been but little explored from the point of view of its earthworm fauna. It is also important to notice that the greater proportion of the entire list of species recorded here are peculiar to the mainland, and do not, so far as is known at present, occur upon the islands of the Malay Archipelago; these latter are regarded by Michaelsen, and apparently w1th justice, as the headquarters of the genus Amyntas. Further to the west, though still in the Oriental Region of zoogeographers, the genus becomes scarcer and scarcer, the forms occurring in India itself and in Ceylon being but very rarely peculiar forms2, and being far from numerous altogether. It is interesting to find that the condition hitherto peculiar to A. stelleri, A. phakellotheca, and A. biserialis, of an increased number of spermatheca? in each segment, is also characteristic of A. minutus and A. polytheca described as new species in the present communication. The interest lies of course partly in the more widely-spread occurrence of this geoscolecid characteristic, but also in the fact that small species like the tw7o described heie may show a character w7hich is more intelligible in a large species such as A. stelleri, where there is more room for a reduplication of these organs. Another novelty of structure for the group w7hich is recorded in the present communication, is the curious intersegmental position, and the single row, of numerous genital papillae, which is the principal characteristic of the new species A. evansi. I am not aware that any closely similar arrangement of such papillae occurs elsewhere among Earthworms of this genus. The large size of the various organs belonging to the reproductive system is, as a very general rule, a marked feature in the 1 P. Z. S. 1900, p. 609. 2 In Ceylon there is only A. taprobanm (Beddard, P. Z. S. 1892, p. 163) and iu India rceogrieonnssi as n od(n Flaeyrd eaA rn.bo ,ta fiJoe.ux Bnaodnm debrlsiae yw( hNBeaertde.d. a Hrids,t .P .So Zc.. Sxi.. 1p9.0 04,3 5b)e,l wohw)i,c ha nodcc Aur. itnr tahvoasne |