518 



RUMINANTIA. 



"pricket" puts forth a simple "dag" or 

 cylindrical shaft (a, /%. 34-0.), which is slightly 

 bent forward. In the third year the branch- 

 ing commences, and he is said to be a "sorel" 

 (). The antlers in the fourth year grow 

 more numerous, and the stem is bifid at the 

 summit (c) ; at this period the Fallow Deer is 



3-iO. 



Development of the horns in the Fallow Deer. (From 

 Cuvier.) 



entitled a " sore" by sportsmen. After this 

 date the upper part of the brain or shaft 

 becomes more palmated, and irregular serra- 

 tions or " snags " are produced at the margin 

 (<7) ; the animal is now a " buck of the first 

 head," and, as age advances, the snags en- 

 large, and take on, more or less, the appear- 

 ance of true antlers. In the Rein Deer the 

 horns undergo a similar metamorphosis ; they 

 are of great size in both sexes, but are some- 

 what less branched and slender in the fe- 

 male ; the brow-antlers are much prolonged 

 forward over the forehead. 



The nature of the anatomical change 

 which takes place in the adult individual 

 during the periodical renewal of the antlers, 

 is characterised by, and contemporaneous 

 with, the following phenomena ; a strong 

 determination of blood to the head takes 

 place at the spring of the year, and the 

 vessels surrounding the frontal apophyses 

 enlarge. This increased vascular action re- 

 sults in the secretion of a fibre-cartilagi- 

 nous matrix, manifesting itself externally 

 by a budding, commencing at the summit of 

 the " core," at the spot where the horns of 

 the previous season had separated. In the 

 early condition the horn is soft and yielding, 

 and it is protected only by a highly vascular 

 periosteum and delicate integument, the cu- 

 ticular portion of the latter being represented 

 by numerous fine hairs, closely arranged. 

 From this circumstance the skin is here 

 termed the " velvet." As development goes 

 on, a progressive consolidation is effected, 

 the ossification proceeds from the centre to 

 the circumference and a medullary cavity is 

 ultimately produced. While this is taking 

 place a corresponding change is observed at 

 the surface. The periosteal veins acquire an 

 enormous size and by their presence occasion 

 the formation of grooves on the subjacent 

 bone. At the same time osseous tubercles, 

 of ivory hardness, appear at the base of the 



stem ; these coalesce by degrees and enclose 

 within their folds the great superficial vas- 

 cular trunks, which are thus rendered imper- 

 vious. The supply of nutriment being cut 

 off, the first stage of exuviation is accom- 

 plished by the consequent shrivelling up and 

 decay of the periosteal and integumentary 

 envelopes. The full growth of the horns is 

 now consummated, and the animals, being 

 aware of their strength, endeavour to com- 

 plete the desquammation by rubbing them 

 against any hard substances which may lie in 

 their path ; this action is technically termed 

 " burnishing." After the rutting season the 

 horns are shed, to be again renewed in the 

 ensuing spring. 



The disposition of the horns is invariably 

 symmetrical in a state of health, but the 

 antlers are sometimes disproportionate on 

 either side and their growth incomplete from 

 deteriorating circumstances. A remarkable 

 sympathy exists between the generative or- 

 gans and the horns, and any imperfection in 

 the one induces a corresponding change in 

 the other. In consequence of this reciprocal 

 influence, the development of the horn may 

 be arrested and the periodical shedding pre- 

 vented by castration. An illustration of this 

 is to be seen in the cranium of a Fallow Deer 

 preserved in the College of Surgeons' Mu- 

 seum, London. The horns of ruminants are 

 seldom more than two in number, but ex- 

 ceptions occur in the case of the extinct 

 Bramatherium and gigantic Sivatherium (Jig. 

 34-1.) found in the tertiary deposits of Northern 

 Fig. 341. 



Front view of the cranium of the Sivatherium. (From 

 a model in the Lond. Coll. Surg. Museum.) 



India. Living instances of more than a 

 single pair are seen in the Four-horned Goat 

 and Many-horned Sheep ; also in the Jung- 

 liburka Antelope (A. subquadricornutus) where 

 the anterior pair are rudimentary, and in the 

 Chousingha (A.quadricorvis), several species of 

 which have been described by authors(y?g.342.). 

 The structure of the horn in Cavicornua is 

 exceedingly simple. The frontal " apophy- 

 ses " or " cores," instead of branching, form 

 cylindrical shafts, more or less solid, the 

 surface being protected by the ordinary peri- 

 osteum, and by an extension of true skin, the 

 cuticular portion of which is developed into 

 a dense horny sheath (fig. 333.). If a trans- 

 verse section be carried through the base of 

 the "core," a number of cavities will be ex- 

 posed, \vhich are continuations of the frontal 



