126 FOSSIL ESTHERLE. 



hexagonal pits, with something like the pattern of the outside of a thimble, an orna- 

 ment common among bivalved Entromostracans. These specimens, though numerous, 

 are scarcely ever clearly exposed out of the matrix on all sides, so it is difficult to get at 

 their real outline, which seems to be just that of C. (?) Bogersii. (See woodcut, fig. 12.) 

 One, and perhaps two, of the last-named species occurs on the same block, 

 Fig. 12. but in a different layer. As is the case sometimes with C. Forbesii, these 

 J§§k carapaces lie crowded together, for the most part parallel or nearly so one 

 I: \ with another, a circumstance due, perhaps, to the action of a slight current 



in the water at the bottom of which they were deposited. 

 V u y This is probably the so-called "granulate" species referred to by Rogers 



Camiona(?) and Wheatley (see above, p. 94). 



S^SIita 9 " What I have stated at PP- 91 and 92 res P ectin g the probability of the 



Magnified 30 c hi e f Estheriaii and Carbonaceous shales of North Carolina, Virginia, and 



diameters. ' o ' 



Pennsylvania, being on one geological horizon, and of the upper Estherian 

 shales of Deep River being of essentially the same age, though separated from the others 

 by upwards of 1800 feet of bedded rocks, 1 will apply to the Cyprida now under notice. 



Whether or not these deposits have a Keuperian character, as Prof. O. Heer's 

 late determination of the Coal-plants from Richmond, Va., seems to indicate, there is 

 no doubt of their being the products of lagoons in the Lower Mesozoic period, and 

 contemporary either with the marine formation intermediate to the Trias and Lias, 2 

 namely, the Rhaetic, or with the Upper Trias itself, and exactly equivalent to the Letten- 

 Kohle 3 (carbonaceous shales at the base of the Keuper). 



7. Candona (?) globosa, Duff, sp. PI. V, figs. 23, 24. 



Cypris globosa, Duff. Geology of Moray, 18-12, p. 16. 

 Length, ^j inch. Breadth, ^ inch. 



Carapace sub-cylindrical, smooth ; carapace-valves oblong, straight on the ventral 

 edge, slightly arched on the dorsal, rounded at the ends, but obliquely at the antero- 

 dorsal region, so that the fore end is narrower {nan the other. Lucid spots (muscle-mark) 

 apparent, like those of Candona Forbesii (' Monog. Tert. Entom.,' p. 18). 



1 Usually regarded as of that vertical thickness (see note, p. 91). 



2 The coal-beds of Steierdorf, Banat, appears to belong either to the Lower Lias or the Rhsetic 

 formation. 



s See above, pp. 4G, 49, &c. I am strongly inclined to coincide with Mr. Hislop in his views as to 

 the age of the beds in India that have yielded Estheria Mangaliensis (see p. 78), and to regard them as 

 " Upper Triassic" (p. 79), instead of "Rhaetic" (p. 81), if we must find an exact European equivalent 

 for them. 



