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Show 1904.] MALAGASY HAT MYZOPODA AURITA. 5 temminckii in its proportions and the angle at which it is set. It is even less expanded across the ilia, which are rounded instead of being concave above. Its length, dorsally, is 9 mm.; its breadth at the acetabulum 5*4, and in front across the ilia 3‘8 ; its depth from front to back 4'6. The symphysis is more slender, though still firmly ossified, and the obturator foramen is smaller. The pectineal process is unusually slightly developed, far less than in any Bat that I have had the opportunity of examining, and is indeed hardly to be called a process. In its entirety, therefore, the skeleton of Myzopoda is remarkable for the simplicity and non-specialisation of the different parts. In all other Bats' skeletons that I have examined (not, I confess, a very large number, but still representing most of the groups) there are some specialisations, such as unusual ankyloses or peculiar development and expansions of processes, but in Myzopoda none of these are present, while even normal Chiropterous characters, such as the elongation of the coracoid and the pectineal process on the pelvis, are at a minimum. It will be evident from the above description, from those of Milne-Edwards, Grandidier, and Dobson, and from the figures now published, that Myzopoda is a most remarkable and peculiar kind of Bat, and that it must certainly form a special Family, the Myzopodidce, though the affinities of this Family are by no means clear. Both Milne-Edwards and Dobson referred Myzopoda to the Vespertilionidte, forming of it a group equivalent in value to the Plecoti, Vespertiliones, and Miniopteri. Now, however, that Mr. Miller has taken Natalus and Thyroptera out of the Yesper-tilionid; e *, the chief reason for leaving it in that Family has been removed, for it is only to those genera that Myzopoda could be supposed to be related. On the whole, it appears to me probable that Myzopoda is most nearly related to the Natalidte and Mormoopidaj f , being a descendant-specialised in some characters and primitive in others-of the common ancestors of those groups. The occurrence of sucking-disks both in Myzopoda and Thyroptera is no doubt a coincidence, for these organs would appear to be comparatively recent specialisations. On the other hand, the possession of three phalanges in the middle finger in the same two genera is presumably a primitive character, for both Phyllo-stomatidse and Mormoopidae possess three, and the loss of the third one in Natalus and Furipterus of the Natalidse J is one of the characters in which that Family shows an approach to the still more highly-developed Yespertilionidfe. # " History and Characters of the Family Natalidae," Am. Nat. xii. p. 245 (1899). f As has already been done by various other authors, I would regard the " Lobostomince " of Dobson as forming a Family distinct from the Phyllostomatidae. J Mr. Miller states that the long terminal phalanx of the two-phalanged Natalus and Furipterus " is divided into two in Thyroptera" but without very definite embryological evidence it would be difficult to accept this homologisation. The terminal bar of cartilage beyond the second phalanx in the Vespertilionidae is a hint at a different homology, and one more in accordance with the usual ideas on the subject. |