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. Tacouic System: Elliptocephalus cmiphoides Emm. OLennx 

 ijibbosus Dalm. Paradoxiden bohemkus. Atopic trilineatus 'Emm. Micro- 

 discus n. g., M. quadrlcostalus u. sp. 



Crustacea: Conocephalus striatus. Ifarpex. Acidanpis. Trinucleus con- 

 centrkus. Calymene aetmria Conrad . Trlanthrus beckil Green. Phacoji.^ 

 calUctphaluH. Illaentts crasskauda, I. trcntonensis. Imtelus gkjas. OgygUi 

 velmta. Acidaspis trcntonenmii. Ceraiirus pleurexanihemii.% C. vigilant'. 

 Beyrkhia aimpkx Jones, B. reguUirifi n. sp., B. ciUata n. sp. AgnosUis 

 lobalus. Cytherina snbeUiptka n.ap., C. crenulata n. sp., C. subcylindrka 

 n. sp. Dikelocephahm minncsotcnsis Owens. lUaenus arcfurus Hall. 

 Asaphun marginalix. Imtelm canalix. Amphun obtumx. Calymene conradi 

 n. sp. L/chas trentoiiensin, etc. 



Manual of geology, designed for the use of 



colleges and academies. New York, 1860. 



Paradoxldes? quadrispinosus. tig. 57; P. nuwrocephalus tig. 70; Atops 

 punctaius, fig. 71; Mkrodhcus quadrkostatm, fig. 73; C'alymene 8enaria,f\g. 

 87; IllcRnus trentouensis, fig. 89 (a); /. crasskauda, fig. 89 (b); Triarthrus 

 beckit, figs. 89 (c) and 91; hotelus gigax, fig. 89 (d); Beyrkhia, Cytherinu, 

 Cyproidea, tig. 90; Trinucleun caractaci, tig. 93 (1); Hcmicripturus, fig. 97 

 (2); IllctnuH barriemis, fig. 98 (3); Dalnumia Hdemirux, fig. 118 (1); Phacopx 

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

 (2); Cyphanpin girardeauensiR, tig. 145(2); HomulonoUix 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,: Atoj/x 

 punctatus, Elliptocephalus (Paradoxldes) asaphoides, Paradoxides thompsoni, 

 P. vermonti, P. macrocephalus, P. ( Pagura) quadrixpinosnx, and Microdix- 

 cus quadricostatus." 



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

 Paradoxides (Pagura) qnadricostatus. 



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

 logica quam consensu et auctoritate amplissimi philos- 

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



