XX 
INTRODUCTION. 
States have produced no Trilobites, their Crustacean fossils being mostly Phyl- 
LOCARiDA. They are; 
/Sf tjlonurus 9 (EcJt 'movaris ?) Wviglitianus. 
Cemtiocans Beecheri. 
Cerat iocaris i .simplex. 
EcJdnocari.s W?i itfieldi. 
Ech inocaris .sublmiiis. 
Echlnocaris pustulosa. 
Echinocaris multinodosa. 
Mesothyra Oceani. 
S'pathiocaris Einersoni. 
Dli^terocarls ^nmice-BcBdaU. 
Blpterocarls pes-cervw. 
Palwopalasmon Neicherryi. 
Chemung group. 
In the sandstones of this period the Trilobites are represented by two 
species, Phacops nupera (see page 27) and Cyphaspis Iczvis; the Xiphosura, by 
the species Protolimulus Eriensis; the Eurypterida, by Eurypterus Beecheri; the 
Phyllocarida, by: 
Echinocaris condylepis. 
Echinocaris socialis. 
Elymocaris .siliqua. 
Tropidocaris bicarinata 
The CiRRiPEDiA are represented by Turrilepas (?) Newberryi; making a total of 
eleven species. 
Tropidocaris mterriipta. 
Dlpterocaris Procne. 
D ipterocaris pes-cer vw. 
Catskill group. 
The sandstones of the town of Andes, Delaware county, and of Meshoppen, 
Wyoming county, Pennsylvania, have furnished specimens of the only known 
Crustacean from this formation, Siylonurus excelsior. 
