186/.] MR. ST. GEORGE MIVART ON THE LEMURIDiE. 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 prsemaxilla 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, but 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 Man) 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 4v0 



of the tibia 430 



of the OS calcis -yj 



■ — of the cuboides ... "41 



At the Jardin des Plantes are also preserved the skeletons of Chei- 

 royaleus milil and of Microcebus jmsitlus. 



The former is the typical specimen of the genus Cheirogaleus ; 

 aud the latter is the type of the genus Microcebus, being the speci- 

 men wbich was ultimately named Microcebus rufus by Geoffroy St. 

 Hilaire*. 



In my former paper I expressed a doubt as to whether the genus 

 Microcebus would not have to be merged altogether in the older 

 genus Cheirogaleus f. The examination, then, of these two typica; 

 specimens should go far to decide this question ; for if they show 

 well-marked and not inconsiderable differences, then the generic di- 

 stinction 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 I'Hist. Nat. Mamm. Ie90n vi. p. 26, 1828. That author liad, how- 

 ever, previously named it pusillus (see Mag. Encyc. i. p. 48, 1776). 

 t P. Z. S. 1861, p. 61 'J. 



