VERTEBRAL COLUMN 



151 



The bodies of the lumbar vertebrae are decidedly flattened dorso-ventrally, 

 and increase in width from first to last. The length increases to the sixth. The 

 transverse processes are plate-like and are directed forward and downward. Their 

 length increases to the fifth and sixth. They form no joints with each other or 

 with the sacrum. Their extremities are enlarged, with the exception of the last. 

 The accessory processes project backward over the posterior notches of the first 

 five. The anterior articular processes are large, compressed laterally, and bear 



Fig. 115.^ — Skeleton of Dog, Lateral View. 

 a, Cranium; b, face; c, mandible; 1H-7H, cervical vertebrae; ISB, last thoracic vertebra; 1L-7L, lumbar 

 vertebrae; K, sacrum; iS, coccygeal vertebrse; 1R-13R, ribs; R.kn., costal cartilages; St., .«ternum; d, scapula; d', 

 supraspinous fossa; d", infraspinous fossa; i, spine of scapula; ;2, acromion; S, tuberosity of scapula; 3', articular 

 end of scapula; e, humerus; -^, head of humerus; 5, external tuberosity of humerus; 5', deltoid ridge; 6, 6', epicon- 

 dyles of humerus; 7, external condyloid crest; 7', coronoid fossa; /, radius; g, ulna; 8, olecranon; 9, "beak" of 

 ulna; /i, carpus; /', metacarpus; A', proximal phalanges; Z, middle phalanges; »;, distal phalanges; n, sesamoid; p, 

 ilium; 10, wing of ilium; 11, shaft of ilium; 12, crest of ilium; 13, external angle of ilium (tuber coxa;); 14, inter- 

 nal angle of ilium (tuber sacrale); 75, superior ischiatic spine; q, pubis; r, ischium; 7&, tuber ischii; 77, acetabulum; 

 S, femur; IS, head of femur; 19, trochanter major; 20, trochanter minor; 21, trochanter tertius; 22, 23, con- 

 dyles; 24, 25, epicondyles; 26, trochlea; t, patella; u, tibia; ^, tuberosity of tibia; 28, 29, condyles of tibia; 

 SO, internal malleolus; v, fibula; 31, external malleolus; 32, head of fibula; w, tarsus; x, metatarsus; ?/, phal- 

 anges; S3, occipital bone; 34, paramastoid (styloid) process; SB, parietal bone; 36, frontal bone; .37, lacrimal 

 bone; 38, malar bone; 39, squamous temporal; 40, maxilla; 40' , infraorbital foramen; 4'i , premaxilla; 42, 

 nasal bone; 4^, external auditory meatus; 44. canine tooth; 45, masseteric fossa; 46, angular process of man- 

 dible. (After Ellenberger, in Leisering's Atlas.) 



mammillary processes. The spinous processes are broad below, narrower above, 

 and with the exception of the last, incline a little forward. Their height diminishes 

 behind the fourth. 



The sacrum results from the early fusion of three vertebriE. It is short, 

 wide, and quadrangular. The spines are fused to form a median crest, which is 

 notched, however, between the summits of the spines. On either side are two 

 tubercles, vestiges of the fused articular processes. The pelvic surface is deeply 



