Raymonp.— New and Old Silurian Trilobites. 
10. 
PLATE 4. 
Cheirurus dilitatus Raymond. The holotype. From the Waldron shale, 
Waldron, Indiana. Natural size. M. C. Z. 628. . 
Cheirurus patens Raymond. The holotype. From the Niagaran at 
Cicero, Illinois. Natural size. M. C. Z. 629. 
Cheirurus dilutatus Raymond. A pygidium from the Waldron shale. 
S22 UME, Cai. AZ TS: 
Cheirurus niagarensis Hall. Cephalon and part of thorax from Wauwa- 
tosa, Wisc. Natural size. M.C. Z. 627. 
The same species. A pygidium from the Rochester shale at Rochester, 
NOY X84. SM. © 2 624: 
The same species. An hypostoma from Wauwatosa, Wisc. Natural 
size. M.C. Z. 1278. 
Cheirurus welleri Raymond. A cotype. Wauwatosa, Wisc. Natural 
size. M.C. Z. 14. 
The same species. The other cotype. The same specimen is shown in 
Plate 3, fig. 6. Wauwatosa, Wisc. xX $. M.C. Z. 630. 
Cheirurus niagarensis Hall. A pygidium from Wauwatosa, Wise. X 2. 
M. C. Z. 1277. 
Cheirurus welleri Raymond. An hypostoma. Wauwatosa, Wisc. The 
specimen is attached to a glabella. 1.45. M.C. Z. 1269. 
