PLATE XXIX 

 PLEURODICTYUM LENTICULARE HALL (PAGES 423,424) 



FIGURE 1. Outline of calices of specimen Plate XXVIII, figure 2; 

 showing central primary cell and seven peripheral calices numbered in 

 the order of their development. X 3^. 



FIGURE 2. The same ; side view. 



Lower Helderberg Group, Albany county, New York. 



