126 PROF. E. RAY LANKESTER ON [Feb. 5, 



3. On the Existence of Rudimentary Antlers in the Okapi. 

 By E. Ray Lankbster, M.A., D.Sc, LL.U., F.R.S., 

 F.Z.S., Director of the British Musenm (Natural His- 

 tory). 



LReceived February o, 1907.] 



(Plates VI. & YII.* and Text-figures 49-55.) 



We know a great deal more as to the horns of the Okapi than 

 was the case when I communicated my description of that animal 

 to the Society in 1901, and founded the genus Okapia. 



The two skulls sent home by Sir Harry Johnston — the first 

 seen in Europe — were hornless, and it was at first a raatter of 

 doubt as to whether the Okapi was a hornless Giraifid, or whether 

 the male possessed horns whilst these two skulls were the one 

 immature and the other that of a hornless female. 



During the printing of my memoir additional specimens were 

 received in Brussels, and were transmitted to Dr. Forsyth 

 Major in London for study and description. I saw in Dr. Forsyth 

 Major's possession a fine adult Okapi skull which had a pair of 

 well-developed bony cones rising each by a broad base from the 

 f rentals, of which they appeared to form part. No suture was 

 visible. An outline of this skull was pubHshed in my memoir 

 by kind permission of Dr. Forsyth Major. I also was able to 

 examine and to mention the existence of a cur-ious structure 

 discovered by that gentleman in regard to these ossicusps ; and I 

 described it in the following terms : — " The fine bony cones 

 three inches long, which have made their appearance in the 



Text-fie-. 49. 



Drawing of a fore and aft section through the tip of the ossicone of an adult Okapi 

 in the collection of the Museum of the Congo Independent State. The section 

 and drawing were made by Dr. Forsyth Major. 



The section shows the penetration of transverse fissures from the surface into the 

 interior of the horn-tip. 



<T, dense ivory-like bone ; 6, posteriorly-placed transverse fissure ; c, more anterior 

 transverse fissure (marking off' and presumably about to cut off and detach an 

 anterior segment or plate of bone as a rudimentary " antler ") 



Brussels skull, shoAV no suture at their base, nor any indication 

 of origin as separate cap-like structures. Foi- all that one can see 

 they may be direct outgrowths of the frontal bone itself. Curiously 



* For explanation of the Plates, see p. 134. 



