CRUSTACEA. 
85 
anterior slope of the glabella is broad and nearly vertical, the occipital fur¬ 
row narrow, and the occipital ring broad upon the axis, arched, and bearing 
at its center two long, divergent spines which are curved downward and 
slightly inward toward their tips. In the single specimen observed which 
retains one sj)ine apparently entire, its length is nearly equal to the length 
of the cephalon. 
Eye-lobes small, inconspicuous. 
Surface bearing tubercles which are closely disposed over the frontal lobe, 
but are scattered or obsolescent on the lateral lobes. On the posterior slope 
of the frontal lobe these tubercles appear to be arranged in two longitudinal 
rows of three or four each. The spines of the head shield are covered with 
acute pustules and granules. 
Dimensions. Two individuals afford the following measurements ; 
(0 (>') 
Length_ 13 mm. 6 mm. 
Width between the eyes__ 14 mm. 8 mm. 
Height_ 10 mm. 6 mm. 
Length of occipital spine_ 13 mm. _ 
Distribution. Upper Helderberg group. Corniferous limestone, Schoharie, 
Schoharie county; in the decomposed chert boulders, Canandaigua, Ontario 
county. 
Ltchas (Ceratolichas) dragon, n. sp. 
PLATE XIX B, FIGS. 14-17. 
Acidaspis, n. sp. ? Hall. Illustrations of Devonian Fossils, pi. xix, figs. 2, 3 (not fig. 1). 1876. 
Two fragmentary Cephala which agree in general features with the preceding 
species show some important variations, as follows; the frontal margin is more 
transverse, the marginal sulcus broader, the frontal lobe slightly more elevated 
and apparently bearing two pairs of strong spines on the posterior edge. Of 
these two pairs, the stronger have their bases wide apart near the margin of 
the lobe, and the other shorter pair is situated behind and within the former. 
