126 THE OX TRIBE. 



time gradually produced. But whatever the causes may 

 have been, their effects rapidly disappear by the inter- 

 mixture of the breeds, and are entirely lost at the end of 

 a few generations. This intermixture and its results 

 would alone furnish a sufficient proof of identity of origin; 

 which, consequently, scarcely requires the confirmation to 

 be derived from the perfect agreement of their internal 

 structure, and of all the more essential particulars of their 

 external confirmation. These, however, are not wanting; 

 not only is their anatomical structure the same, but the 

 form of their heads, which affords the only certain means 

 of distinguishing the actual species of this genus from each 

 other, presents no difference whatever. In both the fore- 

 head is flat, or more properly slightly depressed; nearly 

 square in its outline, its height being equal to its breadth ; 

 and bounded above by a prominent line, forming an 

 angular protuberance, passing directly across the skull 

 between the bases of the horns. The only circumstances 

 in fact in which the two animals differ, consists in the 

 fatty hump on the shoulders of the Zebu, and in the some- 

 what more slender and delicate make of its legs." 



In a scientific work, it is not sufficient for the author 

 merely to make an assertion ; it is not even sufficient for 

 him to say that he has made an experiment or observation, 

 and merely give the result ; he should, in every case where 

 it is practicable, describe the nature of his experiment, 

 the when, the where, the how ; and the means and 

 opportunity he had of making his observations, that the 

 curious or sceptical inquirer may be enabled to perform 

 the experiment, or make the observation for himself. 



Mr. Bennett tells us, that the differences observable in 

 the Indian Ox and the Common Ox "rapidly disappear 



