58 CALIFORNIA ACADEMY OF SCIENCES. 



- American Geology, containing a statement of 

 the principles of the science, with full illustrations of 

 the characteristic American fossils. Vol. 1, Parts I, II 

 and VI. Albany, 1855-57, atlas, 17 pis. 



This incomplete work only appeared in three parts, as enumerated 

 above. 



Trilobites. laconic System: Elliptocephalus asaphoides Emm. Olewi* 

 gibbosus Dalrn. Paradoxides bohemicus. A tops trilineatus Emm. Micro- 

 discus n. g., M. quadricostatus n. sp. 



Crustacea: Conocephalus striatus. Harpes. Acidaspis. Trinucleus con- 

 centricus. Oalymene senaria Conrad. Trianthrus beckii Green. Phacop* 

 callieephalus. Illaenus crassicauda, I . trentonensis. Isotelus gigas. Ogygiv- 

 vetusta. Acidaspis trentonensis. Ceraurus pleurexanthemus, C. vigilan*. 

 Beyrichia simplex Jones, B. regular is n. sp., B. ciliata n. sp. Agnostii* 

 lobatus. Cytherina subelliptica n. sp., C . crenulata 11. sp., C '. subcylindricci 

 11. sp. Dikelocephalus minnesotensis Owens. Illaenus arcturus Hall. 

 Asaphus marginalis. Isotelus canalis. Asciphus obtusus. Calymene conradi 

 n. sp. Lichas trentonensis, etc. 



Manual of geology, designed for the use of 



colleges and academies. New York, 1860. 



Paradoxides? quadrispinosus. fig. 57; P. macrocephalus fig. 70; Atop* 

 punciatus, fig. 71; Microdiscus quadricostatus, fig. 73; Caiymene senaria, fig. 

 87; Illmnus trentonensis, fig. 89 (a); /. crassicauda, fig. 89 (b); Triarthrti* 

 beckii, figs. 89 (c) and 91; Isotelus gigas, fig. 89 (d); Beyrichia, Cytherina, 

 Cyproides, fig. 90; Trinucleus caractaci, fig. 93 (1); Hemicripturus, fig. 9" 

 (2); Illctnus barriensis, fig. 98 (3); Dalmania selenurus, fig. 118 (1); Phacop* 

 bufo, fig. 124 (6); Dalmania calliteles, fig. 124 (7); Phacops nupera, fig. 138 

 (2); Cyphaspis fjirardeauensis, fig. 145(2); Homalonotus dekayi, figs. 134, 

 135. 



Note A, p. 280, the author remarks: " We now know the following trilo- 

 bites, all of which belong to a slate beneath the Calciferous, viz,: Ato)>* 

 punctatus, Elliptocephalus (Paradoxides) asaphoides, Paradoxides thompsoni. 

 P. vermonti, P. macrocephalus, P. (Pagura) quadrispinosus, and Microdis- 

 cus quadricostatus. " 



Dr. Emmons misprints Peltura and uses it in a subgeneric sense to 

 Paradoxides (Pagura) quadricostatus. 



Emmrich (H. F.) De Trilobitis Dissertatio petrefacto- 

 logica quam consensu et auctoritate amplissimi philos- 

 ophorum ordinis, etc. Berolini, 1839, 1 pi., 56 pp. 



