KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 35. N:o 3. 13 



Instaiicos of this kind are, auioug others, Ceroicapra (u/uncd and jjci^haps sonie uf the 

 species of Cohus in whieli the tips of the horns are more or less strongly recurved for- 

 wards. Othei- cobs must, as is seems, use their horns differently. I have had no 

 opportunity to prepare sections of horns of the genus Cobus, but an exteriör inspection 

 of the horns of Cohus elUpsiprynuius ])roves that these horns are conipressed from the 

 sides. They are thus strengthened in the sagittal plane. The same seems also to be 

 the case with several other species of the same genus, to judge from the figures in 

 »The Book of Antelopes». ^) A common feature of the horns of these animals is that 

 they are strongly ringed in front. As several species of Cobus have much longer and 

 larger horns than those of Cercieapru it might be possible that the structui'e of the coves 

 has become moditied in one way or the other (in order to lessen their weight) from the 

 rather primitive condition retained in Cervicajjra nrundinum as described above. The 

 horn-cores of Cobus ellipsiprymnus are so strongly compressed from the sides that 

 the transversal diameter in a specimen only measured 50 mm., but the sagittal one 

 70 mm. 



Passing from the Ccroicaprina^ to the Antilopince we lind also aniong the latter forms 

 which have retained a more or less primitive structure, at least of the coi"e. in this 

 respect Sau/a is perhaps the most simple (conf. Pl. I tig. .5). A section tlirough its core 

 proves the latter to be quite solid, there is no sinus and no loose spongiosa. It consists 

 only of compact bony tissue which is perforated by a number of tine canals and longi- 

 tudinal pores for the blood vessels. Basally these are collected in a central group. In 

 other parts they are rather evenly distributed although perhaps a little more numerous 

 and somewhat larger in the central portion of the posterior half. In the distal fourth 

 of the core the tissue is not quite as dense as elsewhere. It can, however, hardly be 

 called spongious in the proper sense of the word, because the interspaces are minute 

 and the net-\vork thick. The peripherical surface of the coi-e is longitudinally fiuted and 

 small ridges on the inner side of the hoi-ny sheath fit into these fine grooves. Basalh' 

 the sheath is ^•ery thin, but its thickness increases rapidly in a distal direction. This is 

 most conspicuous on the a.uterior side where basally the thickness between the rings is 

 hardly 1 mm., but at the end of the core (that is in the specimen at hand 15 cm. from 

 the base) 9 mm. The posterior side of the sheath is not so thick by far as the anterior, 

 its greatest thickness distally beiiig oidy H mm., the ]'ings not counted in either case. 

 The rings are also stronger and broader anteriorly. They are complete all around. By 

 means of stronger growth of the anterior side during the låter part of life the main 

 direction of the horns is curved backwards a little. but as the tips are directed somewhat 

 forward the uneven growth has been different at an earlier period. It is stated that the 

 Sai(/(i-hucks use their horns as weapons. To judge from the direction of the distal tips 

 it seems probable that they, 4n such cases, deal their blows from above down\\'ards, or 

 from behind forwards. The anterior side is then strained and the posterior pressed. 

 It is therefore appropriate that the elastic horny sheath is thicker anteriorly and the pressure 

 is mainly received by the solid core. The latter has, however, to resist the greatest 



^) ScLATEE and Thomas; Part VI and VII. 



