PALEONTOLOGY OF NEW YORK. 



r . A „DOME« consisting of a short, triangular caudal plate, which is produced 

 : . telson, having a length somewhat greater than that 

 ,„,.,,. The cercopods have about the same length. 



A single specimen of average size retaining the parts in con- 

 junction affords the following measurements: 



Body. Cephalothorax. Abdomen. Post-abdomen. 



Length 29 mm. 9 mm. 9 mm. 11mm. 



Width .-- 6mm - 2mm - 



This very distinctly defim d Echinocarid finds no close ally among the known 



Some points of similarity in general form and outline are suggested 



y the species /.'. ptistulosa and E. sublavis, Whitfield, but specific differences 



in the number and disposition of the carinas and the shape of the nodes are 



lily apparent. Its comparative abundance, at the single locality where it is 



known to occur, is interesting and in consonance with the known gregarious 



habits of both fossil and recenl forms of such crustaceans. 



D Iribution. Chemung group. " In the shales at the base of this group as 

 exposed at Warren, Pa.; belonging to the upper strata of the series when 

 jidered in illation to the entire thickness of the group in New York and 

 nsylvania." (Beecher, he. tit.) 



ECHINOCARIS SUBLJEV1S. 



PLATE XXIX, KIGS 11-13. 



Forms of Fossil Crustacea, etc. Am. Jour. Science, 3d ser.,vol'. xix, 

 pi. (unpublished), figs. 4, 5 and 6. 1880. 



Allies of Nebalia. Am. Naturalist, p. 952, fig. 11. Dec. 1882. 

 M N. Amer. Phyllopod Crustacea. Twelfth Rept. U. S. Geol. Surv., 



!50, 151, fig. Tlli L883. 

 br. Cei ii from the Chemung and Waverly groups, etc. Second Geol. 



Surv. Penna., vol. PPP, p. 5. 1884. 

 and Woodward. Notes on Phyllopodiform Crustaceans referable to the genus 

 1 Dec. iii, vol. i. No. 9, p. 2. pi. xiii, figs. 3, 4 and 5. 1884. 



IB, W ward and Jones. Third Rept. Com. on Fossil Phyllopoda of the 



Palseozoic Rocks, p. 35. 1885. 



Outline obliquely sub-ovate, length to width as 3 to 2. 

 ilarlv convex in front, evenly convex behind. Hinge-line 



