TRUANIA. 



497 



A. splendens (Shad.) Ralfs. (in Pritch., p. 840; Actinophenia 



splendens Shad., T.M.S., 1854, ii., p. 16 ; H.V.H. Atl., pi. 119, f. 1, 2, and 4* ; 

 Type No. 511), plate 22, fig. 649. 



Valve with 12 to 20 compartments, rising gently from the middle up to the 

 margin, where a costa separates each compartment from the adjoining; 

 furnished with a submarginal band, apparently smooth (in consequence of being 

 placed out of focus) ; costse having a small spine at their marginal apex ; 

 umbilicus dentate, with teeth truncate, each dentlet corresponding with the 

 base portion of a compartment. Alveolar lamina feebly developed, inferior 

 lamina with very distinct puncta in quincunx, foiming about 12 striae in 1 

 c.d.m. Diameter of valve, 7 to 18 c.d.m. 



Marine. Found in the same localities as the preceding, but is not so common. 



GENUS 158. TRUANIA PANT., 1886. 



Valve disciform, with strong 

 puncta, divided into cuneate com- 

 partments by the interposition of 

 raised plicae. Umbilical area 

 covered with coarse scattered blurs. 



This genus only comprises a single 

 form T. ArcJiangelskiana Pant, from 

 Archangel, Russia, a figure of which is 

 given (fig. 238) drawn from my photo- 

 graph, taken from the original specimen 



Fig. 238. rntania Archangehkiana, of the author. 



GENUS 159. ACTINODISCUS GREV., 1863. 



Valves very finely punctate 

 throughout their surface, with the 

 elevated portions finishing in an edge 

 (which gives the appearance of 

 spokes of a wheel), and terminated 

 by a coarse ocellus or pseudo- 

 nodule. 



This genus includes two species, A 

 Barbadensis Grev., (fig. 239) found in 

 the fossil deposits of Barbadoes and 

 Fig. 2s 9 .AcHnodiscus Barbadensi* Oamaru, and A. Atlaniicus Kain and 

 Schultze, which has only 4-6 rays, and is found in a fossil state at 



Atlantic City, "New Jersey, U.S.A. 



11 



