144 
PALEONTOLOGY OF NEW YORK. 
Distribution. Upper Helderberg group. From the decomposed chert boulders 
of the Corniferous limestone: Canandaigua and East Bloomfield, Ontario 
county. 
Cyphaspis diadema, n, sp. 
PLATE XXIV, FIG. 13. 
A SINGLE example of this species showing only the intra-sutural portion of the 
cephalon has been observed. 
Cephalon minute; length and width equal; curve of the anterior margin an 
arc with its center at the middle of the occipital annulation; frontal area 
broad, gently convex and slightly appressed about the glabellar margins, 
depressed medially and reflexed upward to the marginal rim. 
Facial Sutures normal. 
Glabella one-half the length of the cephalon, elongate, sub-elliptical; basal 
lobes obscure ; antero-lateral impressions discernible. Palpebral lobes prom¬ 
inent. 
Surface minutely pustulose upon the glabella, the palpebral lobes and on 
the frontal area close to the glabella. About half way from the anterior 
extremity of the glabella to the frontal margin is a single row of minute but 
isolated and distinct tubercles, parallel to the frontal margin. This feature 
is characteristic and will serve to distinguish the species. 
Dimensions. The single specimen has the following size; length 1.7 mm., 
width 2 mm. 
Distribution. Upper Helderberg group. Corniferous limestone : From the 
boulders of decomposed chert, Canandaigua, Ontario county. 
Cyphaspis hybrida, n. sp. 
PLATE XXIV, PIG. 14. 
Intra-sutural portion of the cephalon only observed. Outline regularly 
arcuate; length and width equal; frontal area concave, elevated at the 
margin to nearly the height of the glabella. Border broad, thickened. 
Facial Sutures normal. 
