MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES, VOL. VIM, 5TH MEM. 



PLATE X. 



p. I). / 



91 



x 



Fig. 39. 



P. T. 



P- a. 



Fig. 88. 



Fig. .37. 



I', ap. 



- 1- 



p. V. a. I 



Fig. 36. 



Fig. 40. 



L. E. GfllFFIN, OEL. 



