672 MESSES. Bi C. A. WIXDLE AlSiD V. G. fABSOlfS ON [DeC. 1?, 



the sternum and for 15 inches from it (31), Owen (XIII.) 

 describes two distinct tendons and tliree fleshy belHes in the 

 interval between the sternum and hyoid, while Joly and Lavocat 

 (XII.) say that there are many tendinous intersections. 



In the Bovidse the arrangement is inconstant in the Ox and 

 Sheep. Chauveau (II.) says there is no tendinous intersection ; 

 but in the Duiker-bok (49) we found the sterno-hyoid and sterno- 

 thyroid united into a single muscle with a short central tendon. 

 Near the thyroid cartilage a small slip was delaminated from the 

 main mass for the hyoid bone. In the Mouflon (45) and Fat- 

 tailed Sheep (43) we failed to Hud any trace of the sterno-hyoid. 



In the Tapiridse (52, 54) the muscle was separate and human 

 m its attachments. 



In the Equidse (56, 61) the sterno-hyoids of opposite sides are 

 fused with the tw o sterno-thyroids, and have the same arrangement 

 that we have already described in the Duiker-bok, only the central 

 tendon is much longer. In the Ass (61) the fused mass is pro- 

 portionally much slighter than in the Horse. 



In the Procaviidfe (68) the muscles are quite distinct from one 

 another and from the sterno-thyroids and rise from the dorsal 

 surface of the triangular cartilaginous forward projection of the 

 sternum. The insertion is normal (67, 68). 



In the Elephantidae (74, 76) the sterno-hyoid is absent. 



Prom the foregoing it will be seen that in the Hyrax and Tapir, 

 \\'hich are regarded as archaic types, this muscle has the general- 

 ized mammalian arrangement ; but in the more specialized Ungu- 

 lates the sterno-hyoid tends to fuse with its fellow and with the 

 sterno-thyroid, and in some instances, such as the Elephant and 

 Sheep, to be altogether absent as a separate muscle. In animals 

 with long necks, such as the Giraffe, Horse, and Antelope, one or 

 more tendons are developed in the course of the muscle 



tSterao-thiiroid. — It has already been pointed out how often the 

 sterno-hyoid and thyroid are fused, and in these cases the sterno- 

 thyroid seems to form by far the greater part of the combined 

 muscle. In the Pig (4, 6) the sterno-thyroid is sometimes a 

 double muscle, at other times it splits to be inserted into the 

 thyroid cartilage in two bundles. It is supplied by the ansa 

 cervicis. 



Thyro'hyoid, — This muscle always seems to have the usual 

 mammalian attachments from the thyroid cartilage to the thyro- 

 hyal. Its nerve-supply is the hypoglossal. 



Omo-liyoid. — In the Hippopotamus (1, 2) the omo-hyo.id runs 

 from the hyoid bone to blend with the cephalo-humeral muscle in 

 the neck. In the Pig (4, 5, 11) among the Suidse the hinder 

 attachment of the muscle is, as in so many Ungulates, from the fascia 

 attaching it to the transverse processes of the middle cervical 

 vertebrae. In the Babirusa (12) and Peccary (14), however, a more 

 generalized arrangement is found, and the muscle is continued on to 

 the venter of the scapula. In the Tragulidee (20, 21), Cervidae(25, 

 7, 28), Giraflidai (29, 31), and Bovidje (32, 33, 35, 39, 40, 46, 47, 



