RUMINANTIA. 



543 



symmetrical as in the Horse ; the cerebellum 

 is divided into several irregularly disposed 

 lobules of variable size.* The base of the 

 brain is more flattened than in Man. In the 

 Giraffe the cerebrum lies on the same level as 

 the cerebellum, and does not overlap it (fig. 

 365.). | i The anterior pair of the corpora 

 quadrigemina are paramount in most if not in 

 all the species. The corpora mammilaria are 

 of considerable size. The lateral ventricles 

 intercommunicate. All the nerves at the 

 base of the cerebrum are conspicuously large, 

 especially the olfactories, which form broad 

 bulbous expansions in front, where they are 

 applied to the cribriform plates of the ethmoid 

 bone. The spinal chord and nerves are chiefly 

 remarkable for their length in certain genera ; 

 in the Giraffe the filaments entering into the 

 composition of the anterior and posterior 

 nervous roots of the chord, are widely sepa- 

 rated from one another at their origins. 



Organ of vision. In common with many 

 other quadrupeds, ruminants are provided 

 with an Harderian gland; it is situated at the 

 inner angle of the eye, and opens by a single 

 duct behind the so-called membrana nictitans 

 or third eyelid. The glanduks lacrymahs are 

 lobulated.' The eyeballs are placed wide 

 apart, and are particularly prominent in 

 Camelidae and in .the Giraffe, enabling these 

 animals to look straight in a backward 

 direction without turning the head. The 

 pupillary aperture is oblong transversely, as 

 in Cetacea and Solipeda, the latter family 

 having flocculent masses developed from the 

 uvea which project into the anterior chamber. 

 The most striking feature of the ruminant eye- 

 ball arises from the presence of a tapetum, 

 provided with an extremely brilliant metallic 

 lustre, varying in tints of yellow, green, blue, 

 violet, and purple. 



Organ of hearing. The essential part of 

 the auditory apparatus is similar in construc- 

 tion throughout the entire mammiferous 

 series ; but the external auricular appendages 

 are largely developed in Ruminantia, and 

 moved by a numerous and complicated set of 

 muscles : these have already been referred to. 

 Internally, a small sessamoid bone is some- 

 times found in connection with the stapedius 

 muscle of the Ox. In ruminants generally, 

 the cochlea scarcely exhibits the same amount 

 of turning as in man, the number of coils 

 being rather less than two and a half; in the 

 Chamois only two whorls are present. Minor 



* The design and scope of the present article for- 

 bid our entering minutely upon the Comparative 

 Anatomy of the Brain and some other organs of 

 special interest. We cannot, however, quit this 

 part of our subject without referring to the import- 

 ant Memoirs of M. Camille Dareste, in the Ann. des 

 Sc. Nat., on the "Convolutions of the Brain in 

 Mammifera," and more particularly to his third 

 Memoir (Xo. 2., torn, iii., serie iv.). In this paper 

 M. Dareste shows that the complicated arrange- 

 ments exhibited by these organs in the different 

 ruminant families, may be all reduced to a simple 

 tvpe, and this typical condition he has beautifully 

 illustrated (in his second Memoir) by a description 

 of the actual appearances found in the brain of the 

 Javanese Musk. 



differences exist in the form of the semi- 

 circular canals ; in the Camelidae and Caprese 

 their curvature is elliptical, and in Antelopidae 

 it forms the segment of a spiral ; in Solipeda 

 the curve is parabolic. In the first of these 

 families the canals are particularly spacious. 

 The tympanum in Bovidae is irregular in form, 

 and made up of numerous cells ; these are 

 absent in (Egosceridae, where the cavity is 

 farther distinguished by its capaciousness. 



Organ of smell. The olfactory sense is 

 very highly developed in the present family, 

 but the organic modifications are unimportant, 

 except in so far as they refer to a correspond- 

 ing structural increase. An interesting and 

 special provision, however, is formed in the 

 Camel for the protection of the schneiderian 

 membrane from the injurious effects of the 

 tornado, during which, particles of sand are 

 driven along the deserts with great violence ; 

 the nasal aperture instead of being patent, 

 assumes the form of a narrow cleft, and to 

 ensure its temporary closure, a subcutaneous 

 sphincter muscle is placed at the entrance, 

 subject to the control of the animal's will ; 

 under ordinary circumstances the nostril is 

 well guarded with stiff bristly hairs. The 

 openings of the cribriform lamellae of the os 

 ethmoides are particularly large, and the 

 inferior turbinated bones are enormously 

 developed and folded longitudinally into seve- 

 ral gyrations. In most species the nasal, 

 maxillary, and other cranial sinuses are very 

 extensive. 



Urinary organs. The only peculiarities 

 worthy of remark under this head have re- 

 ference to the imperfectly lobulated character 

 of the kidneys in Bovidae, and the large size 

 of the urinary bladder in ruminants generally, 

 the latter feature being a characteristic of all 

 herbivorous quadrupeds. The glandular bodies 

 situated towards the inner side of the renal 

 organs are more or less oval and elongated. 



Reproductive system. The male sexual 

 organs exhibit few departures from the or- 

 dinary mammiferous type. The testes, as in 

 Solipeda and Man, are enclosed within a scro- 

 tum, which is pendulous, and divided by a thin 

 cellular septum. The gland itself is invariably 

 egg-shaped, its longitudinal extension being 

 considerably increased by the projecting 

 epididymis above and the globus major below. 

 It is more significantly characterised by the 

 presence of a corpus highmorianum, which is 

 essentially a production of the tunica albu- 

 ginea, traversing the organ lengthways, and 

 giving off numerous aponeurotic bands, the 

 latter radiating inwards between the seminal 

 tubes and separating them into lobular bun- 

 dles. The tunica vaginalis is continuous 

 with the abdominal cavity. The vesicuke 

 seminales are largely developed, and exhibit 

 two lateral horns which have a globular form 

 in (Egosceridae and Cervidae. These lobes 

 are by some described as prostatic ; but 

 others regard a narrow glandular layer, lying 

 immediately in front of the above, as the 

 representative of the last-named structure. 

 In the Ram the vasa deferentia unite near 



