CRUSTACEA. 
41 
postero-lateral spines, (b) the lateral margin is not spinose, (c) the termination 
of the axis is connected by an angular ridge with the margin. 
Distribution. Upper Helderberg group. Schoharie grit, Schoharie, Schoharie 
county. 
[s.-G.] CRYPH^US, Green. 1837. 
Dalmanites (Cryph^us) comis, n. sp. 
PLATE.XVIa, fig. 1. 
A SMALL and somewhat incomplete pygidium indicates an undescribed species 
of this sub-genus. It is characterized by the narrow axis curving slightly 
inward on the margins, and bearing six annulations, four distinct and elevated, 
and the last two faintly defined. The pleurm are moderately broad, sloping 
somewhat abruptly toward the margins, and bear five annulations, each of 
which terminates in a short, blunt spinule, with the apex directed backward. 
Whether or not there was a terminal spinule, as in the other American species, 
cannot be determined from this specimen. The pygidium has a length of 
4 mm. and a width of 5 mm. 
Distribution. In the decomposed chert of the Corniferous limestone, Walpole, 
Province of Ontario. 
Dalmanites (Cryph^us) Pleione. 
PLATE XVI A, FIG. 2. 
Dalmania Pleione, Hall. Descr. New Species of Fossils, etc., p. 62. 1861. 
Balmania Pleione, Hall. Fifteenth Rejit. N. Y. State Cab. Nat. Hist., ji. 90. 1862. 
Dalmanites Pleione, Hall. Illusti-ations of Devonian Fossils, pi. xvi, fig. 17. 1876. 
CrypJicBus Pleione, Kayser. Abhandl. z. Geol. Specialkarte von Preussen, etc.. Band ii, Heft 4, p. 33. 1878 
The imperfect pygidium which served as the original of this species is closely 
similar in general proportions, number of annulations and marginal spines to that 
of D. Boothi var. Calliteles. The spines however are relatively longer, more slen¬ 
der, rounder and more distant than in the mature individuals of the variety 
mentioned, but have a striking similarity to the pygidia of the young of that 
form. Our knowledge of the species in America is at present limited to the 
