Page:Second Geological Survey of Pennsylvania Report of Progress PPP.djvu/35

Fig. 12.	A fragment of shale preserving the remains of fifteen young individuals, nine of which are to be seen on the side represented in the figure. Chemung group ; Warren, Pa.
Echinaris Punctata , Hall.
Page 6.
Fig 13.	A nearly entire individual showing the form and relation of the parts, and the number of naked abdominal segments.
" 14.	An enrolled specimen, with the valves partially opened and the abdomen extended along the ventrum. The specimen shows in a very satisfactory manner the optic spots, the number and distribution of the nodes, and the limits of the cephalic region.
" 15.	id. Lateral view, showing the position of the abdomen in this example. The specimen is flattened, and does not represent the normal convexity of the valves.
" 16.	The ventral side of zu. specimen preserving the mandibles in situ. Hamilton group ; New York.
PLATE II.
Elymocaris siliqua,Beecher.
Page 13.
Fig 1.	A specimen wanting the anterior portion of the carpace, but preserving the abdomen and telson, with its appendages.
" 2.	The carnpace with the valves sepearted, showing their form with the rounded elevations and optic nodes on the Cephalic portion. Chemung group ; Warren, Pa.