164 
PALEONTOLOGY OF NEW YORK. 
of the Genesee epoch. The fossils originally illustrated in association with this 
species (Sixteenth Kept. N. Y. State Cab. Nat. Hist., figs. 4, 5 and 6, he. cit.), and 
at the time of the publication of the description, regarded as detached caudal 
spines of larger individuals of the same species, prove to be specimens of the 
pteropod Coleolus aciculum, Hall. An undescribed species bearing very long and 
slender caudal spines is, however, known to occur in this formation, and it is 
probably distinct from Ceratiocaris longicanda. This undetermined species is 
the one referred by Clarke {loc. cit.) to Ceratiocaris longicaudus. 
Distribution. Hamilton group. Genesee shales ; Bristol, Ontario county. 
Ceratiocaris Beecheri. 
PLATE XXXI, FIG. 3. 
Ceratiocaris Beectiei'i, Clarke. Bull. U. S. Geol. Surv., No. 16, Higher Devonian Faunas of Ontario county, 
N. Y., p. 44, pi. ii, fig. 1. 188,^. 
The original of this species consists of the two posterior abdominal somites 
and the post-abdomen, no additional examples having been observed. The 
specimen has been flattened in a soft shale, and its surface ornamentation not 
distinctly preserved. There appear to be no lateral or marginal spines upon 
the somites and the species is therefore referred to the genus Ceratiocaris. 
Of the two abdominal somites the anterior is relatively short, with anterior 
and posterior margins slightly incurved. Its length is 3 mm., and its width 
6.5 mm. The posterior somite is longer, measuring 8 mm. in length and 
5 mm. in width. The caudal plate is sub-triangular on the dorsal surface; 
the telson rather stout, 10 mm. in length; the cercopods, of which a portion 
of one is wanting, a little longer. All these spines are carinate, the telson 
along the middle and the cercopods on their lateral margins. 
Distribution. In the Cashaqua shales of the Portage group as originally 
limited (“ Naples beds,” of Clarke). Son Yea, Livingston county. 
