98 



G. J. de Fe j er vary : 



annual renewment and their intimate relation vvith the 

 integument are circumstances pointing very much indeed towards 

 a more recent corial origin. It is not impossible that the speci- 

 mens described by Mr. Rhumbler are more or less pathologic 

 monstr uosties, and that the axial element , considered by Mr. R h u m b - 

 1er as the os cornu proper, is merely an anomalously detached 

 part of the external ,,sheet", in which case the antlers ought to be 

 considered, to their whole extent (i. e. the ,,sheet" as well as the 

 ,,axis"), ashomologaof the ossacornuum in other Ruminants. Mr. 

 Rhumbler's valuable investigations prove, at any rate, that the 

 portion above the pedicle may, in some way, be genetically 

 independent from the latter, i. e. from the frontal bone, a fact 

 which could easily be considered as proving its independent origin, 

 especially if the other well known morphological and physiological 

 peculiarities of the cervid antlers are simultaneously taken into 

 consideration. Thus, it is not impossible that both the axis and 

 the sheet of the antlers correspond to the os cornu, the histo- 

 genesis of the ,, sheet", viz. of the outer layers, being, however, 

 supplied — by means of their apparently more intimate connexion 

 with the hollow, tube-like pedicle — by cells sent off by the 

 frontal tissue, i. e. especially by those of the pedicle. In this case 

 the antlers ought to be considered as having a mixed histo- 

 genetical origin, in which both, primary and secondary 

 dermal bones, played their role. As regards the anomalously de- 

 tached ,,axis", the natural course of the antlers-sheet's ,, mixed 

 Osteogenesis" might have been, in some way, altered or modified, 

 this alteration resulting in the separate occurrence of ,, axial" and 

 ,, sheet" Clements^ All these combinations are, however, thoroughly 

 hypothetical and theoretical. Only palaeontology and embryology 

 could offer the necessary details on the base of which the problem 

 could be definitively solved. And such suitable researches are as yet 

 wanting. — For the present only the following establishments could 

 be taken for granted: horns and antlers are, by the bulk, homo- 

 logical armaments, both consisting of a proximal apophytic por- 

 tion, derived from a primary dermal bone (the frontal), and a 

 distal e p iphytic portion, represented byasecondarydermal bone 

 (the os cornu); the true starting point of the development of 

 Ruminant armaments has to be searched for in the derm, as 

 stated by Wiedersheim, and not in an exostosis proceeding 

 from the primary dermal bones of the skull, as suggested by Gadow. 



An ethological and bionomical analysis of the natural course 

 of the formation of horn-Hke Clements alone will prove the correct- 

 ness of Wiedersheim's standpoint. The external mechanical 

 irritation to which the first origin of horns and antlers must have 

 been due, acted, eo ipso, in an extero-interior direction, and not 

 contrarily. Thus, if we accept for the origin of the horn-Hke forma- 

 tions the Lamarckian mechanical cause, it is natural that the 

 epidermal and corial tissues were the first to react upon the 



