38 THE SKELETON OF THE HORSE 
The first thoracic vertebra has the following specific characters: The body is 
wide and flattened dorso-ventrally. In front it has a head like the cervical verte- 
Spinous process 
Articular processes 
Facet for tubercle of first rib by’ Transverse process 
—s 
Body 
Fie. 14.—Firsr Tuoracic Vertesra oF Horse, Posrenior View. 
Facet for head of second rib 
brie, and behind a cavity somewhat deeper than any other thoracic vertebra. Two 
large costal facets are found on either side, and a well-marked spine ventrally. 
Fra. 15.—Last Toren THoractc VeERTEBR® OF Horse, Lerr View. 
1, Body; 2, 2, facets for head of rib; 3, facet for tubercle of rib; 4, 4’, articular processes; 5, intervertebral foramen; 
, 5 2,2, 4 ; 
6, mammillary process; 7, spinous process. 
The arch is large and strong, and has large notches. The articular processes are 
much larger than those of other thoracic vertebrae, and resemble a good deal those 
of the seventh cervical. The transverse processes are short and thick, and each 
