The skeleton in the flying lemurs, Galeopteridae / by R.W. Shufeldt.

  • Robert Wilson Shufeldt
Date:
1911
Catalogue details

Licence: In copyright

Credit: The skeleton in the flying lemurs, Galeopteridae / by R.W. Shufeldt. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    of the specimens from the Philippine islands, at least one-third larger on comparing skulls of equal size. (As 144655 $ Basilan Island and 84420 2 Trong, Lower Siam.) This character is constant and eminent- ly distinguishing. One of the most interesting characters on this superior view of the skull is the variation in the extent of the area of the temporal fossae, and the fact as to whether or not they meet in the median line posteriorly, and to what extent, if they do meet. This character 1 have carefully examined in the 52 skulls at hand belonging to the National Museum and the Bureau of Science, and in the few skulls of my own collection. On any specimen the surface of one of the temporal fossae, selecting either side, may be more or less i-ough. In aill forms these areas are very distinctly delined, with the limiting boundary line more or less raised. Now in no Malayan form of flying lemur do the temporal fossai at all a])proach each other posteriorly; the interval often being nearly one centimeter in adult sladls of either sex. This appears to be the case with the young of Cynocepkahi-s (number 144()(!1 2 ) and still more marked in the young of Galeopt.erua. Among the Philip])ine forms this character varies, though in none of them do the temporal fo-ssie ever approach each other anywhere as closely as in any of the Malayan forms. Referring to the numbers in the above tables for the specimens and their localities the following are found to be the intervals between these fossae. In number 144663 it could not be determined as the skull is too much broken up. Of all the skulls from the Philippines the contact is most extensive in number 144655 where the internal margins of the fossa; come in contact for one centimeter, their common borders forming a distinct crest, which extends posteriorly to the occipital crest. In numbers 123422 and 144656, where it is about equal, it is less extensive, the medium crest is less pronounced and does not extend to the occipital crest. The contact is slightly less in number 144658. In numbers 144657 and 14465!) there is an interval of one millimeter, and in num- ber 144660 about two millimeters. The greatest interval is seen in skull number 106 where it is equal to the interval in the Steere specimen in my own collection, that is five millimeters; it is slightly less in number 108, and still less in 105 and 111, the interval still being from one to two millimeters. As a rule, then, the approach of the temporal foss£E, posteriorly, is likely to be far more extensive in Basilan specimens than in those from Bohol; in the latter they are rarely, if ever, in actual contact. Turning to the base of the ci’anium we find the palatal region, or roof of the mouth, comparatively broader and much more in front in the Philippine specimens than in any of the Malayan species; the tympanic bullae are much better developed and have thinner walls in the latter than