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Show 136 MR. K. ANDERSEN ON BATS [May 16, the faunistic affinities of that island ; and it has established itself on the western coast of the Indian Peninsula (gracilis). I have but very little doubt that now, when attention has been called to the differences of all these forms of the minor-type, it will be found also in other parts of the Indian Peninsula. If any inference can be drawn from fragments of a skull and the external characters, the subbadius- type would appear to be an offshoot of the minor-type: already in minor and cornutus the process is a little sharper-pointed than in lepidus; in subbadius and monoceros this tendency is carried much further. The skull of the species of the acuminatus section (Java- Lombok, Sumatra-Engano) is of the lejndus-type; the process too ; the colour remarkably like that of refidgens. This leads me to suppose that acuminatus and its allies (sumatranus, calypso) are scarcely more than giant representatives of the lepidus-type. It is the subbadius-type which, from a zoogeographical point of view, is by far the most interesting : it has spread southwest-wards over a vast part of the Ethiopian Region, and westwards over the Mediterranean countries (1) The empusa-type.- Rh. empusa* and bias'd have progressed further on the way already indicated by Rh. subbadius. They have the small skull and the small teeth characteristic of minor-subbadius ; in the shape of the skull there is no essential difference ; the dentition is identically the same ; the process is that of a subbadius ; the sella is deltoid, that is: the tendency, in the subbadius-sella (as emphasised above), towards assuming a subacute summit has been further developed; and we still see the constriction at the middle of the sella. But empusa and blasii are (as always the Ethiopian and W. Paliearctic species) in several points more highly developed : III.2 is lengthened (about, or more than, 1 ^ the length of III1.); also IV.2 is very much longer (not far from twice the length of IV 1.). Rh. empusa is, however, an inhabitant of Nyasa-land, far S. of the Equator, Rh. blasii of the Mediterranean Subregion; thus, the two extremely closely allied species are now separated by an enormous tract, where no relative appears to occur. As we now know that they are descendants of the Oriental siibbadius-type, the explanation seems to be quite clear : one branch spread soutliwestwards, into the Ethiopian Region, and developed into Rh. empusa (slightly more primitive dentition ; shorter ears, broader horse-shoe); another westwards into the Mediterranean countries, Rh. blasii. There is an instructive fact connected with these two Bats : I believe them to be comparatively recent intruders into their areas ; Rh. empusa is known from one specimen only, from the very East of Tropical Africa; Rh. blasii is much more common in the Eastern Mediterranean tract, and still it does not seem to have reached Spain t. * Andersen, Ann. & Mag. Nat. Hist. (7) xiv. (1904) p. 378 (there is a misprint on p. 380: the length of the mandible is 12'1, not 13'1 mm.). t Not recorded in Cabrera Latorre's " Quir6pteros de Espana," Mem. Soc. Espan. Hist. Nat. ii. (1904). I am also not satisfied that there is any reliable record from the African coast of the Mediterranean. |