LIIfNEAK SOCIETY OF LONDON. 49 



great-great-grandson of " Darley Arabian,"' a horse purchased at 

 Aleppo and shipped to England in 1 705. 



The anthor drew attention to a passage in Darwin's ' Yariation 

 ot" Animals and Plants under Domestication ' (ed. 2, vol. i. p. 52), 

 to the effect that "in various countries horn-like projections 

 have been observed on the frontal bones of the horse : in one 

 case described by Mr. Percival they arose about 2 inches above 

 the orbital processes, and were ' very like those in a calf from 

 five to six mouths' old,' being from half to three-quarters of an 

 inch in length. Azara has described two cases in South America, 

 in which the projections were between 3 or 4 inches in length ; 

 other instances have occurred in Spain."' " The French translator 

 of Azara refers to other cases mentioned by Huzard as having 

 occurred in Spain." 



Dr. Eustace considers that, although both of the two horses 

 that formed the subject of his paper were of a delicate consti- 

 tution, and Lord Rivers's horse died when only four years' old, 

 the prominences cannot be looked upon as exostoses due to disease. 

 He considers the cases to be true instances of " reversion," the 

 reappearance in a rudimentary condition of structures which once 

 existed in a functionally perfect condition. Dr. Eustace is con- 

 sequently led to question the accuracy of the view held by the 

 late Mr. Romanes and others that true bilateral horns are peculiar 

 to, and an evidence of later specialization among the Ruminants ; 

 and he regards it as pi'obable that the possession of horns was a 

 feature of the ancestral stock of the Ungulates prior to the 

 differentiation of the Ruminants and the non-Ruminants. 



LINN. see. PROCEEDINGS, — SESSION 1902-1903. 



