1882.] J. Cockburn — On an abnormality in the horns of the Hog-deer. 45 



The fact, however, that reversion to an extinct ancestor implies degra- 

 dation in the Busince is I confess a difficulty. The Husine type of antler 

 prevailed in Pliocene times, and is a comparatively elementary state. 

 Nevertheless Gervus dicranos, whose antlers are described by Boyd Daw- 

 kins as " so complicated as to defy description," existed during that epoch, 

 The question of the atavism of these Hog-deer antlers is an important 

 one, and as it is notoriously difficult to assign a clear and true value to certain 

 conditions which would entail the destruction of a fancied discovery, I 

 shall jSrst attempt to put in as strong a light as possible the opposite argu- 

 ment to my view, viz, that the horns here described are accidental pro- 

 ductions. 



It may be advanced: Firstly, that of four of the so-called tines only 

 one, the bez, bears any resemblance to a well formed tine, and the fact of 

 its turning down at the tip seems to point to an inherent tendency which 

 the inner tine has (in this species) of curving downwards ; that it is in fact 

 nothing more than the inner tine C arrested in its growth at the- lower 

 portion of the beam. Secondly, that the so-called royal tine is on the 

 inner side of the beam. Finally that the terminal bifurcation is due to 

 a law announced by myself further on, that all terminal portions are 

 capable of furcation. Other abnormalities doubtless exist in private collec- 

 tions of horns and this paper, if it results in no further good, may possibly 

 have the effect of leading to the description of some of these. 



The evolution of antlers in Kuminants appears capable of being brought 

 under a theory of development. The honour of being the first to apply a 

 definite law to the development of the horns of the Cervidce belongs to the 

 late Prof. A. Garrod, who published a paper on the anatomy of the 

 Euminants in the Proceedings of the Zoological Society for January 1877. 

 Garrod's law may be most briefly stated in his own words. " What 

 may be called the typical antler is composed of a bifurcate beam, with a 

 brow-antler springing from the front of its basal portion. These three 

 parts may be termed A, B, and C as in the accompanying diagram (fig. 1.) 

 *' They occur, uncomplicated, in the genus Busa, in G. porcinus, G. axis 

 and G. alfredi (fig. 1). On the assumption that most of the complicated 

 many-pointed antlers that occur are the result of the exaggerated develop- 

 ment of one or other, or both of the extremities B and C, their special 

 features may be explained. For instance imagine both B and C bifurcate, 

 remaining of equal size, and we arrive at the condition found in Gervus 

 schomhurgki (fig. 2). G. duvaucelli differs in that B is extra developed at 



the expense of C (fig. 3) Following out the ingenious hypothesis 



of Mr. Blyth, P. Z. S. 1867, p. 835, G. eldi only differs in the still greater 



development of the anterior branches of B (fig. 4) In Gervus dama, 



and in the species included in the genus Pseudaosis a different condi- 



7 



