144 



SHUFELDT. 



OSTEOLOGY OF THE FLYING LEMURS. 



THE SKULL. 



As has alreadj' been pointed out in the Introduction, there exists 

 considerable variation in the three skulls at hand for examination, which 

 may be due to age, sex, individual variation, or to the skulls having 

 belonged to different species, or to all of these factors more or less 

 combined. Some differences are to be observed even in the case of the 

 two skulls from the Bureau of Science, skulls which, presumably, are 

 from representatives of the same species. The skull from the skeleton 

 collected by Steere evidently belonged to a very old animal, the bones 

 being hard and smooth, with all sutural traces entirely obliterated. 

 Moreover, it is of a clear ocher color and the teeth are considerably worn 

 down. The other two skulls present everj' evidence of haAang belonged 

 to much younger individuals; they are quite white; the dental cusps are 

 sharp, and some of the cranial sutures are still traceable. 



In so far as size is concerned some of the apparent differences can be 

 demonstrated by. measurement, for which purpose the metric system is 

 employed and the results set forth in the following table: 



Measurements of the cranium of Cynocephalus. 



Specimens. 



Extreme 

 length on 



median 

 line from 

 occipital 



crest to 

 anterior 



end of 

 nasal. 



Greatest 

 width: in- 



termalar 

 diameter. 



Inter- 

 apical 

 distance 

 between 

 postor- 

 bital 

 process 

 of frontal 

 and 

 malar. 



Greatest 

 diameter 

 of an or- 

 bital pe- 

 riphery. 



Greatest 

 trans- 

 verse 

 diameter 

 at base of 

 occipital 

 area. 



Median 

 diameter 



from 

 foramen 

 magnum 

 to ante- 

 rior apex 

 of pre- 

 maxil- 



lary 

 spine. 





mm. 

 66 

 63 

 64 



mm. 

 43 

 42 

 45 



10 

 H 

 5 



mm. 

 17 

 17 

 17 



31 

 27 

 30 



61 

 61 

 61 









In some instances, where convenient, in the following description of 

 the skeleton of Cynocephalus, the numbers. 1, 2, and 3, given to the 

 specimens in the above table may be employed to designate the particular 

 skeleton referred to. This Avill consist in placing the number in 

 parentheses after any statement made or character described. 



In form, after the removal of the mandible, the skull is broad, some- 

 ,what compressed from above, do^^oiward, and elongate in the antero- 

 posterior direction. AYhen viewed from above it will be observed that 

 ^he facial portion, anterior to the orbits, contributes very considerably 

 to the marked general breadth of the slmll. Its surface is quite smooth, 

 being broadly convex from side to side, and rounded off , anteriorly, thus 



