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THE AJIEBICAX XATURALIST [Vol. XLVI 



3 and 4). The F, progeny from crosses on grade Dur- 

 ham show the Durham color and other characters to be 

 dominant. The progeny from crosses on native Texas 

 cattle of unknown constitution are very variable. In 

 some cases the F } progeny from the latter resemble the 

 Brahma greatly. However, this apparent dominance of 

 the 'Brahma in many cases, when crossed on native cattle, 

 is probably altogether due to the fact that a considerable 

 proportion of the native cattle already have Brahma 

 characters in them— their immunity to ticks and other de- 

 sirable qualities having favored their perpetuation since 

 the early introduction of the Davis and other Brahma 

 stock. 



Heed Xo. 1 



This herd consists of twenty-five or thirty F x cows 

 i Fig. 5, adults) from a white Brahma sire on grade Dur- 



hams and a few grade Herefords. Twenty-four of these 

 Fj cows were mated to their Brahma-Durham F, half- 

 brother, and eighteen F 2 calves were produced. Of 

 these, six are white and resemble the grandfather white 

 Brahma. One of the calves is shown in Fig. 5, on the 

 right. The remaining twelve F 2 calves from these 

 crosses of hybrid X hybrid resemble the Durham mostly, 



