110 THE GENERAL ANATOMY OF THE TARSII [SECT. A 



(b) From the surface of the tendon of M. flexor longus 

 hallucis : hence perforated tendons pass to digits Nos. 3, 4 and 5. 



(ii) M. flexor digitorum longus (flexor tibialis). This muscle 

 runs almost exclusively to the fifth digit, for which it provides the 

 perforating tendon. No M. quadratus plantae was seen. 



(iii) M. flexor hallucis longus (flexor fibularis). This muscle 

 sends perforating tendons to digits Nos. 2, 3, 4, 5, and it gives rise 

 to the MM. lumbricales. 



These dispositions are so nearly identical with those in the 

 Lemur that no further comment is necessary. The account here 

 given is based on my dissection, but does not in details confirm the 

 descriptions of Burmeister. The chief difference consists in the 

 distribution of the tendon of the flexor tibialis (M. flexor longus 

 digitorum). 



The dorsal interosseous muscles of the foot appear to be 

 disposed about the fourth (i.e. the longest) digit as their axis, 

 I have found no existing record by which to check this state- 

 ment, which represents the condition in the specimen dissected 

 by me. 



A general review of the musculature of Tarsius leads to the 

 conclusion that it is closely related to the Lemuroidea in this 

 respect. The most striking features in Tarsius, such as the 

 enormous size of the M. vastus externus (lateralis) or the M. tibialis 

 anticus are not absolutely distinctive, for they are clearly fore- 

 shadowed even in the true Lemurs, and in the saltatory forms 

 called Galago they approach the degree of specialization attained 

 by them in Tarsius. 



G. Vascular System. The Pericardium is even less exten- 

 sively attached to the Diaphragm than in Lemurs 1 . The aortic 

 arch gives off the great arterial trunks in a sequence and manner 

 identical with that found in Man, so that the higher position of 

 Tarsius in this respect must needs be admitted. The internal carotid 

 artery enters the tympanic bulla in an unusual position (v. supra 

 in the note on the skull), but according to Kampen, the stapedial 

 artery is given off as in the Lemurs. With regard to the arteries 



1 For ;i similar conformation occurring anomalously in Man, ef. Turner, J. A. P. 

 Second Series, 1870, p. 114. 



