PTEROPUS JAVANICUS. 



surface. The canine teeth are long, erect, grooved, and provided at the base, 

 internally, with a semicircular ridge. Of the grinders the first is in most cases only- 

 rudimentary ; the second, third, and fourth have a similar construction ; their surface 

 is greatly compressed. In a lateral point of view, they present anteriorly an elevated 

 point, dechning to the back part of the tooth, where it constitutes an obsolete notch : 

 the anterior elevation is most prominent in the second, and gradually decreases to 

 the fourth. Longitudinally their surface is individually divided by a groove, leaving 

 on each side an elevated triturating ridge, which has been described above as consti- 

 tuting the essential character of this genus. The fifth grinder is minute, nearly 

 triangular, with an even triturating surface. 



In the lower jaw, the front teeth have the same arrangement as in the upper ; 

 but the exterior teeth have double the size and thickness of the intermediate teeth. 

 The canine teeth are shorter than these teeth in the upper jaw, and they are less 

 deeply grooved. The first grinder is minvite and cylindrical, having a single 

 excavation in the middle of its circular surface. The second, third, fourth, and fifth 

 grinders have the same construction as the second, third, and fourth in the upper 

 jaw, and the sixth grinder is small, cylindrical, and even on the surface. 



In attempting to define the specific character of the Pteropus javanicus from a 

 review of the specimens which I brought from Java, I met with perplexities which 

 had not occurred in describing the Pteropus rostratus. These specimens ai-e so 

 diversified in their external marks, that they appeared to belong to distinct species ; 

 but after the most careful examination, I came to the conclusion, that they indicate 

 two strongly marked varieties. One of these corresponds to the specific character 

 placed at the head of this article : the second reqviires a separate description ; and I 

 shall only state at present, that the principal distinction consists in a collar of a lighter 

 brown, inclining to chesnut, and extending entirely around the neck ; in a mixture 

 of brown hairs with the black hairs, both on the back and on the abdomen ; and 

 in a more regularly defined line across the back, separating the brown hairs from the 

 general black colour of the animal. Of the first variety there are four, and of the 

 second five specimens in the Museum. They are suflSciently diversified to shew 

 distinctly that the differences are not the effect of age ; and of each variety there are 

 young and old specimens. The longitudinal ridge on the summit of the cranium 

 affords no distinction, and a careful comparison of the other parts of the skull appears 

 to shew that they belong to the same species. The difficulty of discriminating the 

 species of this strongly marked genus, in consequence of the uniformity of the 

 external marks necessarily employed in defining them, is strongly pointed out by 

 M. Geoffroy : it has occvirred to me, not only in examining the Pteropus javanicus, 

 but also in the review of the individuals of another species, provided Avith short 



