174 ANIMAL MECHANICS. 



Table XX VI I. — Ungulate Biceps and Brachiceus. 





Bic 



rs. 



Brachkt.us. 



Ratio of Force 

 of Bice \s t > 

 Brachiceus. 



Ratio of Con - 

 taction of Dru- 

 chiceus to 13kvi>.s. 



W. 



L. 





1. 





Sq. In. 



In 



Sq. In. 









Nylghau, . 



1.98 



2.85 



0.71 



8*0 



2.3o 



2.8l 



Ass, . . . 



9.72 





°-59 



9.0 



16.47 



7.X3 



Sambur, 



3.16 



3-°9 



0.86 



9-5 



3.67 



3.08 



This Table shows clearly the very different actions of the 

 biceps and brachiceus muscles in the Ungulates. The biceps 

 muscle contracts with a force much greater than that of the 

 brachiceus, while the space through which it acts is much 

 less than that of the brachiceus. The two muscles differ but 

 little in external appearance, but by means of the penniform 

 arrangement of the fibres of the biceps, a rope-like muscle is 

 enabled to do the duty of a flat short muscle, which it would 

 be impossible to place directly upon the bones of the arm. 



The rapid lift of the fore foot, which is so characteristic of 

 the swift Ungulates, and by none more beautifully shown 

 than by the Deer tribe, is mainly due to the powerful action 

 of the biceps through a short space ; while the slower and 

 longer flexions of the forearm are due to the distinctive action 

 of the brachiceus muscle. 



In a Brahmin Cow examined by me, the arrangement of 

 the fibres of the biceps was penniform, though I omitted to 

 measure their length, and the angle made by them with the 

 central fascial sheet of their origin. The measurements of 

 the biceps and brachiceus muscles in this animal were as fol- 

 lows. The biceps weighed 3.88 oz., and had a total length of 

 6 inches The brachimus weighed 2.66 oz., and its fibres, 

 which were arranged as in a prismatic muscle, measured 



