2J2 J. E. WODSEDALEK. 



PLATE III. 



FIG. 7. A transverse section cut near the center of the posterior pair of cavities. 

 FIG. 8. An oblique transverse section cut through the front part of the posterior 

 tube cavities and through the tips of the anterior cavities. 



FIG. 9. A still more anterior view, only the cross sections of the two deeper 

 portions of the anterior cavities being in evidence. 



I 



