70 CALIFORNIA ACADEMY OF SCIENCES. 



2. Homalonotus Koiiig ( Trimerus and Dipleura Green. ) K Dipleura 

 dekayi, B. Trimerus. H. knightii Konig., H. delphinocephilus, H. armatus, 

 H. herschelii. 



3. Cyphaspis Burm. C. clavifrons Dalm. 



4. Phacops Emm. (Pleuracanthus Peltura, Milne Edwards). P.lat- 

 ifrons, P. protuberans, P. anchiops, P. rotundifrons, P. macrophthalmu*, 

 P. odontocephalus, P. sclerops, P. hausmanni, P. caudatus, P. mucronatus, 

 P. archnoides, P. stellifer. 



5. Aeonia Burm. (Calymene Dalm., Asaphus Emm.) A. diops, A. con- 

 cinna Dalm., A. cornuta Goldf. 



6. Illaenus Burm. (Bumastus Aut.) A Illaenus crassicauda, I. gignn- 

 tem Burm. B Bumastus. /. barriensis. 



7. Archegonus Burm. (Illcenus Dalm. Asaphus Emm. Calymene H. 

 v. Mey. Phillipsia~Port.) A Dysplanuscentrotus. B Archegonus cequaHa, 

 A. globiceps. 



8. Asaphus Brong. (Asaphus < Nileus Dalm. Isotelus Dekay. Hemi- 

 crypturus Green). A Nileus Dalm. A. (N.) armadillo Dalm. B A. 

 palpebrosus, A.expansus, A. tyrannus, A. raniceps, A. extenatus, A. pla- 

 tycephalus. 



9. Ampyx Dalm., A. nasutus Dalm., A. mammlllatus Sars., A. rostratus 

 Sars. 



10. Trinucleus Murch. (Cryptolithus Green). T. cataracti, T. granu- 

 latus, T. Jimbriatus, T. ornatus, T. tesseilatus. 



11. Ogygia Brong. O. buchii, 0. guettardi. 



12. Odontopleura Emm. (Acidaspis Murch.) 0. ovata Emm., O. ett'tp- 

 tica Burm. 



13. Arges Goldf. A . armatus Goldf. 



14. Bronteus Goldf. (Goldius DeKon.) B. fiabellifer Goldf., B. signatux 

 Phil., B. laticauda Wai. 



15. Paradoxides Brong. (Olenus Dalm.) P. bohemicus, P. spinulosus. 



16. Olenus Burm. (Paradoxides and Olenus Aut.) 0. gibbosus, 0. 

 tcrabaeoides, O.forficula Sars. 



17. Conocephalus Zenk. C.sulzeri Schloth, C. striatus Emm. 



18. Ellipsocephalus Zenk. E. Hoffi Schloth. 



19. Harpes Goldf. H. ungula. 



Poecilopoda 3. Belinurus Konig, B. trilobitoides Buckl. 



Family 1. Eurypteridae: Eurypterus Dekay, E. remip.es, E. lacustri* 

 Harlan, E. tetragonopthalmus. 



Family 2. Cytherinidae: Cytherina Lam., C. balthica Hisinger, C. pha*- 

 eolus His. 



Carbonformation und Dyas in Nebraska. Dres- 

 den, 1866, 5 pis. 



Phillipsia sp. ? Cythere nebrascensis n. sp., C. cyclas ? Keys var. 



