174 
PALEONTOLOGY OF NEW YORK. 
Thoracic region characterized by a strong transverse node just behind the 
nuchal furrow, acutely tubercled near the hinge-line, and beneath this an 
obscure node extending from this furrow obliquely backward. A lateral 
ridge or carina takes its origin near the anterior portion of the carapace and 
extends backward in a broad sigmoid curve, becoming obsolete near the 
posterior region. Above this carina the postero-dorsal area is gently rounded 
and smooth. 
Surface smooth or minutely punctate. 
Abdomen and telson unknown. 
Dimensions. Three specimens of this species have been observed, and all 
are approximately of the same size, viz.; length 9 mm., width 5 mm. 
Observations. Echinocaris condylepis appears in many respects almost a minia¬ 
ture of Echinocaris punctata of the Hamilton shales. The nodes are essentially 
the same in number and disposition, though less conspicuous ; the lateral carina 
is much shorter, but has the same sigmoid curve; the ridge upon the postero- 
dorsal margin is, however, much more strongly elevated than in the latter 
species and is not tubercled or spinose. The general abbreviation of all the 
features in which it resembles E. punctata is a persistent character, and it will 
serve to distinguish the two species, while it may indicate their common 
genetic origin. 
Distribution. Chemung group. In the soft greenish shales at Philipsburgh 
(now Belmont), Alleghany county. 
Echinocaris socialis. 
PLATE XXX, FIGS. l-]2. 
Echinocaris socialis, Beecher. Ceratiocaridae from the Chemung and Waverly groujis. Second Geol. Surv. 
Penna., vol. PPP, p. 10, pi. i, figs. 1-12. 1884. 
Echinocaris socialis, Etheridge, Woodward and Jones. Third Kept. Committee on Eossil Phyllopoda of 
the Palseozoic Rocks, p. 35 1885. 
Cephalothorax obliquely sub-ovate in outline, widest posteriorly. Length along 
the hinge-line to greatest width as 1 to 1.5; to greatest length as 1 to 1.8. 
