158 



Anatomy of the Rabbit. 



of the articulating portion with the condyloid process, the 

 so-called neck of the mandible (collum mandibulae), is a thin 

 plate of bone, the anterior and posterior margins of which are 

 barely notched by the anterior and posterior mandibular 

 incisures. Connecting the anterior incisure with the rim of che 

 alveolus of the last cheek-tooth there is a deep groove, the sulcus 

 ascendens, the lateral margin of which is formed, by the reduced 

 coronoid process (processus coronoideus). Its low medial margin 



is formed by a bony stay which 

 extends to the medial surface of 

 the horizontal portion opposite the 

 last cheek-tooth, and. is continued 

 forward, into the mylohyoid, line. 

 The sulcus ascendens lodges in the 

 natural condition the insertion 

 portion of the greatly reduced 

 temporalis muscle. 



/net. 



C. 

 THE HYOID APPARATUS. 



Fig. 65. Lateral surface cf the 

 hyoid and larynx: c.a., arytenoid 

 cartilage; c.c, cricoid cartilage; c.i., 

 inferior cornu of thyreoid cartilage; 

 cm., lesser cornu of hyoid; c.mj., greater 

 cornu of hyoid; c.s., superior cornu of 

 thyreoid cartilage; c.t.. left plate of the 

 thyreoid cartilage; e.. epiglottic cartilage; 

 f.t.s., thyreoid foramen; l.h., lateral 

 hyothyreoid ligament; l.h.m., median 

 hyothyreoid ligament; m.ct., cricothy- 

 reoideus muscle; o.h.. hyoid bone; s.m.. 

 stylohyoideus minor muscle; s.mj., stylo- 

 hyoideus major muscle; tr., cartilaginous 

 tracheal r i n u s . 



The hyoid bone (os hyoideum) 

 (Fig. 65) is a stout, somewhat 

 wedge-shaped bone lying in fron t 

 of the larynx and between the 

 angles of the mandible . Its ven- 

 tral portion is connected, with the 

 thyreoid cartilage of the larynx 

 by the median hyothyreoid 

 ligament. With its lateral portion are articulated, two indepen- 

 dent elements, termed the lesser and. greater cornua. The lesser 

 cornu (cornu minus) is a small, partly cartilaginous structure, 

 attached to the anterodorsal angle of the hyoid, and. connected 

 through the stylohyoideus minor muscle with the jugular process 

 of the skull. The greater cornu (cornu majus) is a larger element 

 extending obliquely dorsad, and similarly suspended from the 

 jugu'ar process by the stylohyoideus major muscle. The con- 

 nection of the lesser cornu with the styloid process through the 

 stylohyoideus minor replaces the stylohyoid, ligament of the human 



