4 ARKIV FÖR ZOOLOGI. BAND 3. N:0 14. 



of the skull beliind the antiers, and the neck tliat must be 

 strengtliened in such a case as this and be developed in cor- 

 respondence with the great size and weight of these appen- 

 dages. But the facial portion of the skull has no direct need 

 of being strengthened by an extensive ossification of the 

 vomer in consequence of an iiicreased development of heavy 

 antiers. This is also proved by the fact that the Wapiti, 

 the Elk and several other deer with heavy antiers have the 

 ossification of the vomer very incomplete, while on the other 

 hand several of the Telemetacarpalia with rather small ant- 

 iers are provided with a comparatively extensivety ossified 

 vomer. It may be concluded from this that there is no di- 

 rect and causal correspondence between large antiers and a 

 strong ossification of the vomer, or the contrary. The cause 

 of the extensive ossification of the vomer must therefore lie 

 deeper and the charaeteristic derived from the degree of 

 ossification of this bone among the Cervidce thus gains in im- 

 portance. 



If the comparison between the skulls of Megaceros and 

 the common Fallow Deer is not confined to the vomer, but 

 extended further to other parts, several important differences 

 make themselves known. The most striking of those is per- 

 haps that while the common Fallow Deer has a very large 

 anteorbital vacuity the same of the Giant Deer is almost 

 completely bridged över by bone — at least in the specimen 

 before me — so that only one or a few small openings re- 

 main. This may plainly be seen on fig. 2. This charaeteri- 

 stic appears to be of considerable taxonomic value as all 

 typical deer have »the unossified vacuity extensive» (Lydek- 

 KER 1. c. p. 62). The smallness of the antorbital vacuity of 

 Megaceros reminds about the similar condition of Rangifer 

 in which the antorbital vacuity is greatly reduced in size. 

 And, although it is not always diminished quite to the same 

 degree in the Rein-deer as in the present specimen of Mega- 

 ceros, specimens may be found in which the vacuity is wholly 

 covered by an osseous lamella. 



This is, however, not the only likeness between the Giant 

 Deer and the Rein-deer. The shape of the nasal bones of 

 these two animals is essen tially alike. In both, these bones 

 are broad and flat, strongly expanded posteriorly, and an- 

 teriorly not rising so as to form a nasal ridge ascending 



