672 MESSRS. B. C. A. WIXIVLB AXD F. G. PABSON'S OX [Dec. 17, 



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

 describes two distinct tendons and three fleshy bellies in the 

 interval between the sternum and hyoid, while Joly and Lavocat 

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



In the Bovidae 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 find any trace of the sterno-hyoid. 



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

 m its attachments. 



In the Equida? (5(5, 61) the sterno-h voids of opposite sides are 

 fused with the two 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 Procaviidae ((58) 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 Elephantida; (74, 76) the sterno-hyoid is absent. 



From the foregoing it will be seen that in the Hyraxand Tapir, 

 which 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. 



Sterna-thyroid. — 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 !*• sometimes ;i 

 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- 

 idal. Its nerve-supply is the hypoglossal. 



Omo-hyoid. — In the Hippopotamus (1,2) the omo-hyoid runs 

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

 lb'' neck. In the Pig (4, 5. 1] ) among the Suidae 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 t<> 

 the venter of the scapula. In the Tragulidae (20, 21), Cervida?(25, 

 7. 28), Giraffida?(29, :il ), and Bovid® (32, ■'>■'>. 35, 3!). 40, 46, 47, 



