178 
PALEONTOLOGY OF NEW YORK. 
ing the length of the last three somites of the abdomen. The cercopods are 
somewhat curved near the base of attachment, and have a slightly greater 
length than the telson. 
Dimensions. The carapace of this species measures 17 mm. in length and 
12 mm. in greatest width. The three somites of the abdomen and the telson 
have a length of 13 mm.; of this the first somite measures 1.5 mm. in 
length; the second 1.8 mm.; the third 2 mm.; the telson to the apex of the 
spine 7 mm. 
Distribution. In the calcareous concretions of the Erie shales, a formation 
approximately equivalent to the lower Portage shales of New York. LeRoy, 
Lake county, Ohio. 
Echinocaris pustulosa. 
PLATE XXIX, FIGS. 9, 10. 
Echinocaris imstulosa, Whitfield. Amer. Jour. Science, Third Series, vol. xix. No. 109, p. 38, pi. (unpub¬ 
lished), fig. 7. 1880. 
Echinocaris imsttdosa, Packard. Monog. N. Amer. Phyllopod Crustacea. Twelfth Ann. Kept. U. S. Geol. 
Surv., p. 451. 1883. 
Echinocaris ptistulosa, Beecher. Ceratiocaridae from the Chemung and Waverly groups, etc. Second Geol. 
Surv. Penna., vol. PPP, p. 5. 1884. 
Echinocaris jnistnlosa, Jones and Woodward. Notes on Phyllojiodiform Crustaceans referable to the genus 
Echinocaris, etc. Geol. Mag. Dec. iii, vol. i. No. 9, p. 2, pi. xiii, fig. 6. 1884. 
Echinocaris pustulosa, Etheridge, Woodward and Jones. Third Rei^t. Committee on Fossil Phylloiwda of 
the Palaeozoic Rocks, p. 35. 1885. 
Cephalothorax small, longitudinally sub-ovate; length to width as 3 to 2. 
Surface irregularly convex. Hinge-line short, straight, length less than 
two-thirds the length of the carapace. The anterior extremity is broken 
off in the original specimen, but judging from the position of the nodes 
upon the thoracic portion of the carapace and the indications afforded by 
the broken edge, the anterior margin had probably about the same curvature 
as in the species Echinocaris suhlcevis, although in the original figure it is 
represented as strongl}^ incurving near the hinge. The ventral margin is 
broadly curved at the posterior extremity, bending somewhat abruptly to 
