166 



ANATOMICAL TECSNOLOGT. 



completely divides the artlira] surface of the capitellum into two pai-ts corresponding to 

 the demifacets of the two vertebrae (Fig. 53, Arlhron capitdli). In the cat it but partially 

 divides the surface. In man the ligament joins the intervertebral fibro-cartilage, and does 

 not extend from side to side. In the cat it passes from side to side in a synovial groove 

 lined by an extension of the synovial membrane lining the joints of the capitella of the 

 pair of ribs. Hence, while in man there are four separate synovial cavities for the capitella 

 of each pair of ribs possessing the interarticular ligament, in the cat there is but one, since 

 the arthra of the capitella communicate with each other through the groove for the Liga- 

 mentum interarticulare. 



References.— Bichat, A, 1,231; Mayer, 47, 373; Chauveau, A, 140 ; Leyh, A, 310; 

 Cleland, 4 and 5 ; Quain, A, I, 141 ; Gray, A, 396 ; Gage, 5, 431. 



§ 436. Preparation. — Fig. 50 represents two costse and costi- 

 cartilagines separated from the body and in the position assumed 



during the fullest possible 

 ^^^^^^^bercuLiim. inspiration — that is, drawn 

 ventrad, laterad and cepha- 

 lad so as to obliterate their 

 caudal convexity (Fig. 30), 

 and give the greatest capa- 

 city to the thorax. The 

 cleaning process was carried 

 only sufficiently far to re- 

 move the soft parts, leaving 

 the interarticular ligament 

 and the connections of the 

 costal cartilages and ster- 

 num (§§ 252, 427). 



§ 437. Arthron costicartilagi- 

 nis. — The amphiarthrodial articula- 

 tion between the sternal end of the 

 diaphysis and its cartilage (§ 433). 



§ 438. Arthron mesosternebri 

 — Costo-sternal articulation. — The 

 diarthrodjal articulation of the costal 

 cartilage with the mesosternum. The 

 first costal cartilage articulates with a 

 single sterneber (prsesternum), the 

 other eight with two (§ 430, Fig. 49). 

 § 439. Capitellum— Head.— The 

 vertebral end of the rib ends in a somewhat pear-shaped capitellum or head which articu- 

 lates diarthrodially with the demifacets of two contiguous vertebrse (Fig. 53, Arthron 

 capitelli.) 



§ 440. Cervix— Neck. — The cervix or neck of the rib is the somewhat constricted 

 part immediately following the capitellum and between it and the tuberculum. 



Fig. 50.- 



-CaddalView of the Seventh Paie 

 OF COST..S; (Ribs) ; x 1. 



