The Heart. 



379 



Arrow in the ostium arteriosiim 



^ 



Aorta ascendens 



Cuspis anterior valviilae 

 bicuspidalis [mitral is] 



Arteria pulmonalis 



Ostium venosum ventriculi sinistri 



Conus 

 arteriosus" 



i 



Yeutriculus 

 dexter 



Sulcus longitu-_ 

 dinalis anterior 



Cuspis posterior 

 _ valvulae 

 bicuspidalis 



[mitralisj 



Chordae tendineae 



of the anterior 

 - papillary muscle 

 (out through) 



Posterior papillary muscle 



Trabeculae carneae 



425. Left ventricle (venfriculus sinister) of a distended heart, 



viewed from in front and somewhat from the left. 



(The anterior wall has been almost entirely removed, the left wall partially ; the atria have been 

 cut away. An arrow has been mtroduced into the ostium arteriosum.) (Text see p. 380.) 



The atrium sinistrum (left fore-chamher), (0. T. left auricle) (see Figs. 411 414 

 and 427) is wedge-shaped, broad behind, narrower in front. At the junction of the posterior 

 with the lateral surfaces, right and left, lie the openings of the venae puhnonales. The right 

 wall, formed partly by the septum atriorum, shows frequently the concave margin of the valoula 

 foraminis ovutis (see p. 377). The anterior wall contains the ostium venosum ventriculi sinistri. 

 lYom the junction of the right with the superior wall goes off the zigzag curved auricula 

 sinistra (left auricle of the heart), (0. T. left auricular appendix) which curves around the 

 a. pulmonalis from the left and reaches as far as its anterior surface. This left auricle contains 

 inside it numerous interlacing trabeculae carneae; otherwise the wall of the atrium is smooth inside. 



