CLASS CRUSTACEA. 



FAMILY ACIDASPIDiE.— Acidaspis, Terataspis. 



FAMILY AGLASPID^.— Aglaspis. 



FAMILY AGNOSTID^.— Agnostus, Shumardia. 



FAMILY ASAPHID^.— Asaphus, Bathyurelliis, Bathyurus, Dolichometopus, Ill^enus, 



Illsenurus, Isotelus, Megalaspis, Nileus, Ogygia. 

 FAMILY BRONTEIDiE.-Bronteus. . 



FAMILY CALYMENID^.— Arges, Calymene, Homalonotus. .1., .-.f-*,^' A a It vii 

 FAMILY CERAURIDJE. — Amphion, Cerauriis, Encrinurus, Sphserexochus. 

 FAMILY CONOCEPHALID^.— Conocephalites, Conocoryphe, Crepicephalus, Dicello- 



cephalus, Ptychaspis, Splenopleura. 

 FAMILY CYPHASPID^.-^Cyphas. 



FAMILY CYTHERID^.— Cythere, Cytherina, Cytheropsis. . 



FAMILY EURYPTERID^.— Anthraconectes, Dolichopteris, Eurypterus, Pterygotus. 

 FAMILY HARPEDIDiE.— Harpes, Harpides. 



FAMILY LEPERDITIID^.— Beyrichia, Isochilinia, Leperditia, Primitia. 

 FAMILY LICHASID^.— Lichas. 

 FAMILY PARADOXIDtE. — Agraulos, Anapolenus, Arionellus, Bathynotus, Chario- 



cephalus, Loganellus, Menocephalus, Olenellus, Olenus, Paradoxides, Remopleu- 



rides, Telephus, Triarthrella, Triarthrus. 

 FAMILY PHACOPID^.— Dalmanites, Phacops, Thaleops. A 



FAMILY PROETID^.— Phillipsia, ProBtus. , 'M\^ki^.J.u.-f ^ [cleus. 



FAMILY TRINUCLEID^.— Ampyx, Endymionia, Holometopus, Microdiscus, Trinu- 

 ORDER AMPHIPODA.— Diplostylus. 

 ORDER CIRRHOPODA.— Plumulites. 

 ORDER ISOPODA.— Acanthotelson. 



ORDER MACRURA. — Anthracopalsemon, Archseocaris, Palseocaris. 

 ORDER PHYLLOPODA. — Ceratiocaris, Dithyrocaris, Leaia, Solenocaris. 

 ORDER STOMAPODA.— Amphipeltis. 

 ORDER XYPHOSURA.— Euproops. 

 INCERT^ SEDIS.— Climachtichnites, Diplichnites, Helminthoidichnites, Protichnites, 



Rusichnites. 



Acantholoma, syn. for Acidaspis. 



spinosa, syn. for Acidaspis tuberculata. 

 Acanthotelson, Meek & Worth en, 1860, 



Proc. Acad. Nat. Sci. [Ety. akantha, 



a spine; telson, the end.] 

 eveni. Meek & Worthen, 1868, Am. Jour. 



Sci., voL 46, Coal Meas. [Ety. proper 



name.] 

 iniequalis, syn. for Palaeocaris typus. 

 stimpsoni, Meek & Worthen, 1865, Proc. 



Acad. Nat. Sci., Coal Meas. [Ety. 



proper name.] 



Acidaspis, Murchison, 1839, Sil. Syst. [Ety. 



akis, a spear-point ; aspis, a shield.] 

 anchoralis, S. A. Miller, 1875, Cin. Quar. 



Jour. Sci., Cin. Gr. [Sig. anchor-like.] 

 ceralepta, Anthony, 1838, (Ceratocephala 



ceralepta) Am. Jour. Sci., Cin'ti Gr. 



Not clearly defined, 

 cincinnatiensis, Meek, 1873, Ohio Pal., 

 • vol. 1, Cin'ti Gr. [Ety. proper name.] 

 crosotus, Locke, 1843, Am. Jour. Sci., vol. 



44, Cin'ti Gr. [Ety. crossotosi fringed.] 



The word is misspelled — it should be 



crossota. 



