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Show 186/.] MR. ST. GEORGE MIVART ON THE LEMURIDAE. 961 I found to exhibit all those cranial and dental characters detailed in my former paper, except certain trifling differences resulting from the immature condition of the specimen. This immature condition, however, enables me now to affirm that there is no interparietal bone, and that the praemaxilla is exceedingly small. The cervical region is elongated, and the dorsal region is short; but the neural laminae of the cervical vertebrae do not exceed those of the dorsal vertebrae in antero-posterior extent. The atlas has but one continuous posterior articular surface for the axis; its transverse processes are not large; and it has no neural spine. The axis vertebra has a considerable spinous process, hut it is not produced backwards. All the other cervical vertebrae have small neural spines. There are twelve dorsal and seven lumbar vertebrae, and these much resemble the corresponding vertebrae of Lemur. The scapula closely resembles that of the last-named genus; the carpus is provided with an os intermedium ; and the fourth digit of the manus is the one extending furthest forwards. The ilium is very much like the ilium of Lemur; its posterior inferior (the inferior anterior of M a n ) spinous process is well marked. The femur has a slight indication of a third trochanter, and the patella is elongated. The tarsus is short, and decidedly less than one-third the length of the tibia, showing no approximation to the structure presented by Microcebus pusillus, still less to that of Galago. The fourth digit of the pes projects most. inches. Length of the femur 4*70 - of the tibia 4*30 • of the os calcis *93 of the cuboides *41 At the Jardin des Plantes are also preserved the skeletons of Cheirogaleus milii and of Microcebus pusillus. The former is the typical specimen of the genus Cheirogaleus; and the latter is the type of the genus Microcebus, being the specimen which was ultimately named Microcebus rufus by Geoffroy St. Hilaire*. In m y former paper I expressed a doubt as to whether the genus Microcebus would not have to be merged altogether in the older genus Cheirogaleus^. The examination, then, of these two typical specimens should go far to decide this question ; for if they show well-marked and not inconsiderable differences, then the generic distinction may be provisionally retained, unless some other species be found to exhibit so completely intermediate a structure as to do away with the value of the differential characters. Now, on comparing these two specimens, I find that not only is * Cours de l'Hist. Nat. Mamm. lecon vi. p. 26,1828. That author had, however, previously named it pusillus (see Mag. Encyc. i. p. 48, 1776). f P. Z. S. 1864, p. 619. |