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Show 1905.] OF THE GENUS RHINOLOPHUS. 101 longer than in rouxi, i. e. more than 1§ the length of III.1 (cf. nereis and stheno). V .2 is extremely short. Colour. To judge from specimens preserved in alcohol, probably not far from being the same as in the dark phase of Nepal examples of Rh. rouxi. Skull. The essential characters are as in rouxi, thus proving Rh. thomasi to be an offshoot from that type of Bat, not (as might very well be supposed, in view of the short metacarpals) from borneensis. The skull of Rh. thomasi agrees with that of rouxi in the broad brain-case ; it differs from rouxi in the much smaller size. Compared with borneensis, the skull of Rh. thomasi is as small as in the smallest individuals I have seen of borneensis (even as small as in malayanus), but the brain-case is markedly broader, even broader than in the largest borneensis, and the supraorbital length is exceedingly short (cf. measurements, p. 100). Dentition. p3 external; p2 and p4 in contact; p2 external. Upper canine and p4 in contact. Both of the specimens examined are identical in dentition. Measurements. On p. 100. Type. § ad. (in alcohol). Karin Hills, Burma, 1888. Collected by Signor Leonardo Fea. Presented by Marquis G. Doria. Brit. Mus. no. 90.4.7.10. I venture to connect with this fine species the name of Mr. Oldfield Thomas, who already thirteen years ago (I. s. c.) pointed out that it could scarcely be identified with any hitherto known form, but refrained from describing it as new, owing to the general confused state of this group of Bats. 13. R hinolophus affinis Horsf. (Plate III. figs. 11-13.) Diagnosis. Sella pandurate. p2 in the tooth-row. Forearm 50-56 mm. Details. This species marks an important progress in development as compared with Rh. rouxi. It is the base of the ferrum-equinum section. The chief modifications are four : in the shape of the sella ; in the structure of the wings; in the size of the animal; in the shortening of the palatal bridge. In the borneensis-rouxi type the sella is practically parallel-margined ; in affinis it is pandurate, i. e. the lateral margins concave, as in ferrum-equinum, though generally to a slightly less degree. In simplex and its closest relations the lancet is almost cuneate; in borneensis there is a tendency towards emargination of the lateral margins; in rouxi this tendency is carried to an extreme ; in affinis the lancet falls back to the former stage : it is almost cuneate. Throughout the whole series of forms reviewed above, with the exception of the somewhat aberrant Rh. nereis, stheno, and thomasi, the wings have remained at the same primitive stage : no lengthening of the second phalanx of the third finger. In affinis this phalanx has considerably increased in length, being always more |