108 PROF. E. RAY LANKESTER ON THE [Feb. 5, 



The text-figure 32 also shows that three of the dark hair- bands 

 are disposed around the base of the young ossicone. The great 



Text-fio-. 32. 



Right Horn 

 base 



Right. 



Diagram to show tbe flattened plate-like form and tlie orientation of 

 the horns of the foetal Giraflfe. 



a, b, c, d. The four left-side iiiter-cornual coloiir-bands of the pelage. 



lateral compression or flattening of the young structiu'e is 

 remarkable as compared with the fuller cii'cular contour of a 

 transverse section after ossification has advanced. 



Possible Relations of the Giraffid Ossicones to the hov.y Horn- 

 cores of Bovidce and the Antlers of Gervidce. 



In my memoir describing Sir Harry Johnston's specimens of 

 Okapi, I ventured on some speculations as to the relationships of 

 the bony growths called horns and antlers in the Pecora. These 

 speculations were vitiated by the uncertainty of existing know- 

 ledge as to the actual embryological origin of the structures 

 compared. They assumed the origin of the horn-cores of Bovidse 

 as separate rudiments which become united to the osteogenetic 

 tissue of the frontal bone at an early period of development. 



Although convincing histological accounts of their development 

 are not yet in existence, it seems to result from the observations 

 of Diirst that the horn-cores of Bovidag are not of independent 

 origin, but are actual outgrowths of the osteogenetic tissue of the 

 frontal bone. The same origin appears to hold for the horn-style 

 or column which supports the antler of the Oervidse. 



It is unfortunately the fact that our knowledge of the early 

 embryological history of the "ossicones" of the Girafie and 

 Okapi is still more defective. All we know is (1) that in Owen's 

 newly-born Giraffe the rudimentary unossified ossicone was sepa- 

 rated (as shown in text-fig. 29) by the dense periosteal membrane 

 from the subjacent parietal bone ; (2) that in the foetal specimen 

 of two-thirds time here described the soft forecast of the ossicone 

 was equally cut ofT from the subjacent parietal bone by dense 



