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Show 286 MESSRS. B. c. A. WINDLE AND F. G. PARSONS ON [Nov. 3, crest. In the Hippopotamus (1) and Pig (4) it is very large, in the former reaches back as far as the 10th thoracic vertebra; in the Pig it is divided into a central and lateral bundle, the former of which corresponds to the biventer cervicis of other mammals although no central tendon is present. In the Camel (18), Giraffe (33), and Chevrotain (20) the biventer forms the greater part of the muscle and is really a biventer. In the Ox (36, 37), Sheep (41, 44), and Antelope (55) the two bundles are present, but the inner or biventer does not deserve its name as it has no central tendon. In the Horse (63, 67) the two parts are present, and four oblique myocommata are found intersecting one or both. In the Tapir (55) Murie makes no mention of a biventer, though he certainly knew of the existence of such a muscle. In our own Tapir unfortunately the deep neck-muscles could not be examined. In our specimen of Hyrax (75) the muscle was composed of three distinct parallel bundles; of these the innermost was continuous with the longissimus dorsi, the middle rose from the anterior thoracic transverse processes, while the external came from the articular processes of the hinder cervical vertebra?. All three were inserted together into the occipital bone, and a single myocomma was present in each of the external and internal bundles though not opposite one another. This description differs a good deal from that of Mivart and and Murie (XXIV.) in the Hyrax ; the arrangement they found differs so much from that of any other ungulate that we fancy it must have been abnormal. The Mtdtifidus spince, Interspincdes, and Intertransversales nothing of special importance. The description in Man applies to them very well. Suboccipital Muscles. - These have the usual mammalian arrangement: the posterior (inferior) oblique is very massive, and the rectus capitis dorsalis (posticus) major, as is so frequently the case, is a double muscle consisting of an external and an internal part; the latter Lesbres (V.) calls rectus capitis posticus medius, and he says it is always present in Ungulates. Meckel (VII.), however, says that in the Sheep only a single muscle is present, and we are so far inclined to agree with him that in our specimen (46) we found the separation a very arbitrary one. The Rectus capitis dorsalis (posticus) minor and lateralis fair size and have the attachments as in Man. Triangularis sterni.-This muscle, as Lesbres (V.) remarks, is better developed in the Ungulates than in Man. Its origin is, as usual, from the caudal portion of the dorsal surface of the sternum. In the Chevrotain (20), Duiker-bok (54), and Horse (63) it is inserted from the 2nd to the 8th rib, in the Harnessed Antelope from the 2nd to the 9th. Diaphragm.-This muscle in Ungulates differs in a good many respects from that of Man. The costal origins usually come from about half the total number of ribs, and where they are inserted into the central tendon each digitation can still be distinguished, |