106 THE GENERAL ANATOMY OF THE TARSII [SECT. A 



the example mentioned above. Of the five sacral vertebrae, two 

 articulate with the ossa innominata, though three are fused 

 together. Two more wide vertebrae follow these, and have been 

 reckoned as sacral, for they are contrasted with the narrow (caudal) 

 elements succeeding them. 



The clavicles are relatively large, and are curved slightly but 

 with uniform convexity forwards. 



The rod-like sternum consists of four conjoined pieces. An 

 additional ossified portion follows, and from this a cartilaginous 

 expansion (metasternum) is continued still further caudally. In 

 the dissection of Tarsius, I found a small suprasternal process 

 anterior to the presternum. The scapula is curiously proportioned, 

 being very long and narrow : the coracoid process is falciform (as 

 in the Lemur), and the acromion process is spatulate. The massive 

 humerus has no deltoid eminence, but the outer lip of the bicipital 

 groove is very prominent and elongated, so that possibly it may 

 include that eminence. The inner lip of the groove is slightly 

 developed. 



The radius and ulna exceed the humerus in length and are not 

 bowed apart 1 (as in the Simiidae). 



The carpal bones include an independent os centrale, and the 

 os hamatum surpasses all the others in point of size. The terminal 

 phalanges of the digits are excessively short when compared with 

 the other phalanges or with the metacarpals. The third digit is 

 the longest. 



The os innominatum is narrow and elongated, with a large 

 thyroid foramen and a small blunt ischiatic spine. The symphysis 

 does not extend to the ischia, but is limited to the pubic elements. 

 The narrowness of the pelvis and the obliquity of its anterior 

 aperture (pelvic brim) recall the conditions in the rabbit. 



The femur has a straight shaft, which expands at its condylar 

 end. 



The tibia is long and slender : the head is slightly retroverted, 

 and the shaft markedly platycnemic, as befits an animal of saltatory 

 habits (cf. M. Vallois, op. cit., v. p. 76 supra). The fibula is slender 

 and though free above and below, it seems to be actually fused 

 with the tibia just below the mid-point of its length. 

 1 This does not agree with Burmeister's description. 



