6 EINAR LÖNNBERG, STUDIES ON RUMINANTS. 



Rhaphiceru.s inelanotis Tiiunb. resemble those of Cej)halophu.'i. The length of the core in a 

 speciiiiPii of tho former is ;tbout 60 percent of that of the sheiith. The core is soiiiewhat 

 compre.ssed so that its sagittal diauieter at the buse ineasured 14,5 mm., but tlie trans- 

 versal one only 12,5 mm. Siich an arrangement is of course apt to strengthen the liorn 

 in the plane of attack. This is of course a specialisation wheri compared with the sim])ly 

 conical cores of Cephalo/ihuft. With regard to the inner structure the core of this H/ia,- 

 pliiceniH is just as solid and compact as that of Cephalophus, thus representing the same 

 stage of development. It ought to Ije meiitioned already here that the horns of the young 

 Anoci, sho\v a development almost identical with that of the same organs in Cephalophus 

 as described above. Thej' represent thus a very ])rimitive stage. In a specimen the 

 horny sheaths of which measured 127 mm. the cores are about 100 mm. in length. A 

 longitudinal section through the core of this s]jecimen (conf. tig. 2, Ph I) proves that 

 also the interiör structure of the core agrees with the same in Cephalophus. The core 

 of such a young Aiwa naiuely, is quite solid and consists of compact bony tissue only 

 tra\ersed l)y the canals of the iiourishing bloodvessels. In the full grown animal the 

 structure of the core is different as will be described below, and as Heller ') has re- 

 marked before. 



Although my investigations have not comprised other antelopes with short spikelikc! 

 horns than those mentioned abo\e, it seems quite probable that the structure of the horn 

 cores of all the vinall antelopes of the subfatnilies Cephalophince and Neotraglnoi resembles 

 that found in Cephalojthii-^ and Rhaphicerus. That is, as far as the shape and size of the 

 horns respectively, is just as simple and small as in the examples quoted. Some of the 

 species of the genera Ourehia, Nesotrafji/s and Madoijua \vA\e the horns ridged and some 

 of them rather strongly so, as for instance Madoqua kirki the basal half, and Nesotiuigus 

 liviiu/ston/anus two thirds or even three fourths of the horns. 1 hardly belieNe, however, 

 that this characteristic in these cases has produced any change of the structure of the core. 



From such a ])riraiti\e form and structure ;is that described above the horns of 

 tlie Cacicornia lia\e developed in difterent directions. Although they are spirally 

 twisted the horns of Tragelaphii,s have not advanced very far from tlie ])rimitive type 

 exhibited by the forms described abo\e. The horny sheath is still comparativel_y thin, 

 and the main strength, at least basally, lies in the core. The following statements are 

 taken from a specimen of 7'ra(./elaphus with the length of the horns measuring 26 cm. 

 in a straight line from base to ti]). A longitudinal section proves that the core extends 

 through four tifths of horn. The horny sheath measures at the base in some ])laces only 

 1' 2 or 2 mm. in thickness. Towards the tip of the core this thickness increases to about 

 4 mm. But along the three, more or less jjronounced, spiral ridges of the horn the 

 sheath is thickei' than elsewhere and through the de\'elopment of these the horn is basally 

 triangulär. The most angular of these ridges is the one whicli begins l)asally on the 

 outer (lateral) side and forms its posterior angle. This is already at the base about 

 .1 mm. in thickness. The second in strength, which from its situation may be assumed 

 to l)e phylogenetically first developed, begins basally in front, and somewhat nearer the 



\) Der UrbiiÖel von (Jelebes, Dresden 1889. 



