40 CALIFORNIA ACADEMY OF SCIENCES. 



The author remarks iu regard to Calymene spbufera : "Amoug the 

 specimens of Lower Siluriarf fossils of Missouri in the collection of my 

 friend J. N. Nicollet, Esq., I noticed the tail of this curious trilobite, which 

 has on the back of one of the articulations of the middle lobe an erect 

 curved spine, curved towards the caudal extremity, and more than one- 

 third of an inch in length." 



Conrad's species should replace Cyphaspis girardeaue7isis Shumard, 

 1855. 



— Observations on the lead-bearing; limestone of 



Wisconsin, and descriptions of a new genus of Trilo- 

 bites and fifteen new Silurian fossils. 



In Proc. Acad. Nat. Sci., Phila., vol. 1, 1843, p. 329. 

 Thaleops u. g., T. ovatus u. sp. 



Corda (A. J. C) and Hawle (Ignaz). Prodrom einer 

 Monograpliie der bohniischen Trilobiten. 



In Abhaudl. bijhm. Gesell. Wiss., Prag, vol.5, 1847, pp. 129-292, 7 pis. 



This work is generally attributed to A. J. C. Corda. The 58 new genera 

 described in this work are arranged by Joachim Barrande, Systcme silurien 

 du centre de la Boheme, vol. 1, p. .39, as follows: 



I. Division. Telejurides. 



Phlysacium "| tt i i i -o 



■' - = Hydrocephalus Barr. 



Phanoptes J 



2. Phanoptes 



3. Crithias 



4. Tetracuemis 



5. Gouiacanthus 



6. Enneacnemis 



7. Acanthocnemis \ c, -d 



) = Sao Barr. 



8. Acauthogramma/ 



9. Endogramma 



10. Micropj'ge 



11. Seleuosema 



12. Staurogmus 



13. Hen 



jrse "1 



■raulos J 



Arionellus Barr. 



14. Agrf 



15. Conocorj'phe \ 



16. Ptychoparia > = Conoceplialus Zeuk. 



17. Ctenocejihalus \ 



18. SeleuoiJeltis = Acidaspis Mi;rch. 



19. Polytomurus = Dionide Barr. 



20. Tetrapsellium = Trinucleus Lhwj'd. 



21. Phalacroma = Agnostus (in part) Broug. 



22. Selenoptychus = ^glina Barr. 



23. Mesosi^henisciis = Agnostus integer Beyr. 



