﻿PLATE LL 



Echinoconus globulus, Desor, 1842. 

 From the Upper Chalk. 



Fig. 1 a. Base of the test, natural size. The Rev. T. Wiltshire, F.G.S. (P. 230.) 



b. Posterior view do. do. do. 



c. Lateral do. do. do. do. 



Echinoconus castanea, Bronr/niart, 1842. 

 From the Lower Chalk. 



Fig. 2 a. Upper surface of a large test, natural size. My collection. (P. 215.) 



b. Under do. do. do. 



c. Lateral view do. do. 



d. Posterior do., showing the position of the marginal vent. 



e. Inter-ambulacral and ambulacral plates, and poriferous zone, magnified four 



diameters. 

 /. Do. from basal region. 



g. Apical disc. 



3. A small test of the same species, natural size. 



