CLASS CEUSTACEA. 



FAMILY ACIDASPIDiE.— Acidaspis, Terataspis. 



FAMILY AGLASPIDyE— Aglaapis. 



FAMILY AGNOSTID.E— Agnostus, Shumardia. 



FAMILY ASAPHIDvE.— Asaphus, Bathyurellus, Bathyurus, Dolichometopus, lUfenus, 



Illsenurus, Isotelus, Megalaspis, Nileus, Ogygia. 

 FAMILY BRONTEIDyE.-Bronteus. 



FAMILY CALYMENIDiE.— Arges, Calymene, Homalonotus. 

 FAMILY CEEAURIDjE.— Amphion, Ceraurus, Encrinurus, Spharexochus. 

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



cephalus, Ptychaspis, Solenopleura. 

 FAMILY CYPHASPIDiE.— Cyphas. 



FAMILY CYTHERID^.— Cythere, Cytherina, Cytheropsis. 



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

 FAMILY HARPEDIDiE.— Harpes, Harpides. 



FAMILY LEPERDITIIDjE.— Beyrichia, Isochilinia, Leperditia, Primitia. 

 FAMILY LICHASID^.— Lichas. 

 FAMILY PARADOXIC^.— Agraulos, Anapolenus, Arionellus, Bathynotus, Chario- 



cephalus, Loganellus, I\Ienocephalus, Olenellus, Olenus, Paradoxides, Remopleu- 



rides, Telephus, Triarthrella, Triarthrus. 

 FAMILY PHACOPID^.— Dalmanites, Phacops, Thaleops. 



FAMILY PROETIDjE.— Phillipsia, Proetus. [cleua. 



FAMILY TRINUCLEIDjE. — Ampyx, Endymionia, Holometopus, Microdiscus, Trinu- 

 ORDER AMPHIPODA.— Diplostylus. 

 ORDER CIRRHOPODA.— Plumulites. 

 ORDER ISOPODA.— Acanthotelson. 



ORDER MACRURA.— Anthracopalaemon, Archa50caris, Paleeocaris. 

 ORDER PHYLLOPODA.— Ceratiocaris, Dithyrocaris, Leaia, ^olenocaris. 

 ORDER STOJIAPODA.— Amphipeltis. 

 ORDER XYPHOSURA.— EuprQops. 

 INCERTjE SEDIS. — Climachtichnites, Diplichnites, Helminthoidichnites, Protichnites, 



Rusichnites. 



Acantholoma, syn. for Acidaspis. 



spinosa, syn. for Acidaspis tuberculata. 

 Acanthotelson, Meek & Worthen, 1860, 



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



a spine; t^feon, tlie end.] 

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



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



name.] 

 irucgualis, syn. for Palfeocaris typus. 

 stimpsoni, Meek & Worthen, 1865, Proc. 



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



proper name.] 



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



akis, a spear-point ; a»pis, 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. crossotos, fringed.] 



The word is misspelled — it should be 



crossoto. 



