﻿PLATE XLIX. 



Echinoconus globulus, Desor, 1842. 

 From the Upper Chalk. 



Fig. 1 a. Upper surface of a test, natural size. British Museum. (P. 230.) 



b. Under do. do. do. do. 



c. Lateral view do. do. do. 



d. Posterior view do. do. do. 



e. Inter-ambulacra, ambulacra, and zones, magnified six diameters. 

 /. Apical disc, magnified. 



g. Tubercles of base. 



Echinoconus conicus, Bregnius, 1732. 



Fig. 2 a. Posterior view of a test, natural size. My collection. (P. 221.) 



b. Base of the same showing the relative dimensions of vent and peristome. 



3. Lateral view of another test. 



4. Do. do. 



5. Poriferous zones around the periostome, showing the arrangement of triple 



oblique pairs of pores in that region, magnified four times. 



