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PALEONTOLOGY OF NEW YORK. 
carapace measures 36 mm. in length, inclusive of the prora, and 25 mm. 
over the valve from one lateral margin to the other. 
Observations. Were the slender of this specimen broken away, Rhinocaris 
scaphoptera might readily be taken for a species of Dithyrocaris or Tropidocaris, 
for, although there is no hinge in the carapace, the normal curvature of the 
shield would cause it to yield along the axial line whenever subjected to lateral 
compression. 
Distribution. Hamilton group. In the upper shales of the group, associated 
with Rhinocaris columbina, Echinocaris punctata and Elymocaris capsella: Tiche- 
nor’s Glen, Canandaigua Lake. 
