PROTOPLASMIC, AMGEBIC, AND OTHER MOVEMENTS 325 



PLATE LXXXV 



Fig. 6. 



Fig. 7. 



Fig. 8. 



PLATE LXXXV {cuntimicl) 



Pig. 2. — Photograph of a transverse section by the Author of the right and left ventricles of the heart of a deer, near the base 

 of the ventricles. Shows that the left ventricular cavity {h) is completely closed by the spiral twining of the musculi papillares ; the 

 right ventricular cavity [a) being all but closed. The walls of the left ventricle and septum (J, g, d) are comparatively very much 

 thicker than those of the right ventricle (e). 



Fig. 3. — Photograph of a transverse section by the Author of the left ventricle of the same heart near the apex ; the ventricular 

 cavity being all but occluded by the powerful spiral twining action of the musculi papillares (f, g). 



Fig. 4. — Photograph of a transverse section by the Author of the same ventricle still nearer the apex ; the ventricular cavity 

 being quite obliterated by the strong spiral action of the muscular fibres of the apex. 



Fici. 5. — Photograph of a dissection by the Author of the base of the right and left ventricles of the heart of a heifer after 

 removal of the right and left auricles. Shows the ventricular cavities quite open, and the orifices of the aorta and pulmonary artery 

 partly closed by the semi-lunar valves, a. Right ventricular cavity, open as in diastole ; ft, left ventricular cavity, ditto ; c, 'l, 

 fibrous rings from which certain of the superficial muscular fibres of the ventricles arise ; the deeper fibres being, for the most part, 

 continuous beneath the rings ; e, basal fibres of the right ventricle ; /, ditto of left ventricle ; g, orifice of pulmonary artery with 

 remains of semilunar valve ; h, ditto of aorta ; i, infundibulum. 



Fig. 6. — ^Photograph of a transverse section by the Author of the apices of the right and left ventricles of the heart of a sheep. 

 The apices {v, w) are open as in diastole. The muscular fibres of the left apex are seen winding spirally out of the interior of 

 the left apex in two sets {x, y). The two sets of fibres (c, y) form the beginnings of the two musculi papillares, which pursue spiral 

 courses within the left ventricular cavity. 



