RUMINANTIA. 



509 



is attenuated and compressed. Throughout 

 the whole order there prevails considerable 

 disparity as respects the cranium and face; 

 the bones of the latter occupy fully two- 

 thirds of the entire length of the skull, and 

 the area of the face on section is nearly 

 double that of the cranium. 



Bones of the cranium. Eight bones enter 

 into the composition of the adult cranium ; 

 viz , an occipital, a parietal, two frontal, a 

 sphenoidal, an ethmoidal, and two temporal ; 

 and, in addition to these, some species are 

 provided with two ossa triquetra or inter- 

 parietals. 



Fig. 326 



Skull of the Ox viewed from behind. (From a spe- 

 cimen in Lond. Coll. Surg. Museum.) 



The occipital bone (1 !,./% 326.), as in most 

 of the mammalia, is originally divided into 

 four, one superior, one inferior, and two 

 lateral pieces (11', Jig. 326.). These become 

 early consolidated, and in the calf at the time 

 of birth they are firmly united together and 

 to the parietal and interparietal bones lying 



immediately in front. The occipital crest is 

 prominent in the Llamas, and still more fully 

 developed in the true Camels. In Bovidae the 

 crest corresponding to the occipital is formed 

 by the junction of the parietal and frontal 

 bones, the superior occipital remaining flat. 

 In ruminants generally, the paramastoid pro- 

 cesses (/ Jig. 326.) are much elongated, falci- 

 form, and curved inwards, and between these 

 and the occipital condyles (i) a very deep 

 fossa intervenes. In Camelidae, at the angle 

 formed by the union of the petrous portion 

 of the temporal with the lateral and superior 

 occipitals there is a large opening on either 

 side. In this family the anterior condyloid 

 foramina are of moderate capacity, but in 

 Cervidae they are of great size and some- 

 times four in number, in which case two 

 remain small. In CEgosceridse and Bovidae 

 they are also large and occasionally double. 



The parietal (9*) is single, and with a few 

 trifling variations, is articulated to the cranial 

 bones in the usual manner. The lambdoidal 

 or parieto-occipital suture lies considerably 

 in front of the crest, except in Bovidae, 

 where it lies below, and is separated from 

 the frontal suture by the intercalated and 

 narrow wedge-shaped parietal bone. The 

 (Egosceridae have the parietal in the form of 

 a flattened band, encircling the cranium and 

 extending between the orbitar wings of the 

 sphenoid on either side (b,Jig. 335.). It is 

 broader in the goats than in the sheep. In 

 Bovidae the parietal does not extend so far 

 forward (b. fig. 327.). In the Giraffe the 

 lateral processes of the parietal are narrowed 



Fig. 327. 



Skull of the Ox, viewed laterally. (From Spix.) 



to a mere point, but the body of the bone 

 which reaches from between the horns as far 

 back as the occipital crest has a longitudinal 

 diameter of fully six inches. The coronal or 

 fronto-parietal suture in this species and a 

 few other genera is situated in a line with 

 the osseous protuberances which support the 

 horns. It is most frequently placed behind ; 

 in the Gazelles, however, it appears in front. 

 The frontal bones (8) are of large size and 

 great breadth ; this latter feature being more 

 especially manifest in the Camels, the Sheep, 

 and certain bovine species. In the Came- 

 lidae they extend backward between the 

 anterior divisions of the parietal bone, and in 

 front they are articulated to the lachrymals 



by a transverse suture, which is less extended 

 in the Llamas than in the true Camels. In 

 the Llamas and in the genus Moschus a 

 small part of the frontal is connected to the 

 superior maxillary. There are several supra- 

 orbital or frontal foramina (c) with rounded 

 orifices, which in the Camels are placed near 

 the middle line and at the centre of the fore- 

 head. In the Llamas these openings are 

 placed rather farther back and united by a 

 longitudinal groove. The frontals are ele- 



* The numerals here refer to all the subjoined 

 figures of crania with the exception of figs. 327. 

 and 335. 



