1882.] J. Cockburn — On an abnormality in the horns of the Kog^deer. 47 



" In the mid-Miocene age, the cervine antler consisted of a simple 

 forked crown only. In the Pliocene it becomes larger and longer and 

 altogether more complex, some forms, such as the Cervus dicranios of 

 Nesti, being the most complicated antlers known either in the living or 

 fossil state. These successive changes are analogous to those which are 

 to be observed in the development of the antlers in the living deer, which 

 begin with a simple point and increase their number of tines until their 

 limit be reached." More recently (Nature Nov. 1881) he has repeated the 

 same generalization in slightly different language which I here quote, " In 

 other words the development of antlers indicated at successive and widely 

 separated pages of the geological record is the same as that observed in the 

 history of a single living species." 



Boyd Dawkins regards the antlers of the extinct Procervulus, which is 

 the simplest type hitherto met fossil, as the starting point of the antlered 

 ruminants both in the old and new worlds. But the antlers in this genus 

 were more or less branched, and bearing the existing Goassus rufus in view, 

 they can hardly be regarded as quite elementary. Considering the imperfect 

 state of the Geological record it may be foretold that an antlered ruminant 

 with simple deciduous spikes for horns will yet be discovered fossil. 



Prof. Dawkins has not attempted to apply his theory to an explanation 

 of the horns of existing deer as Garrod had done, but Sir Vincent Brooke 

 who published an elaborate paper on the classification of the Cervidae, with 

 a synopsis of the existing species, in the P. Z. S. for 1878 p. 883, has fol- 

 lowed Garrod's theory closely. 



There is therefore room for an amplification of Dawkins' phylogenetic 

 law, which I would state thus, as bearing on both extinct and existing 

 cervines. 



The developtnent of the antlers of individual species of cervines is 

 a recajntulation of the history of the development of antlers in the group. 



I would assume the typical antler to be a simple spike, as in Coassus 

 rufus, capable of extensive furcation, reduplication, arrest and redundancy 

 of growth in parts. 



In certain species the terminal portions of the main stem, when the 

 limit of length has been reached, have a tendency to develop an almost 

 unlimited number of snags, possibly referable to palmation of the horns in 

 an extinct ancestor. This tendency is markedly manifest in Gervus elaphus 

 and Panolia eldi and in a lesser degree in Bucervus* 



I shall take up the development of the horns of the Wapiti, Gervus 

 canadensis, to illustrate my theory. 



* The fine horns of Biicervus duvaucelU figured by Blyth, P. Z S. 1867, fig. 3, show 

 this character, and also a tendency to palmation. The horns are yet in the Museum. 



