558 Synopsis of the Trilohites of JVorth America. 



refer to all the pages, your readers can examine for themselves, 

 and judge of the value that ought to be attached to Professor 

 Silliman's remarks on matters of science, who has proclaimed 

 magna voce, in his Journal, that 



" Dr. M'Murtrie is entitled to the thanks of the cultivators of 

 natural history, for his vei-y faithful and able translation of this 

 most perfect system of Zoology. The publication of the present 

 work, we are confident mllform an era in this country." — Silli- 

 man^s Journal, V. 21, p. 388. 



A SUBSCRIBER. 



SYNOPSIS OF THE TRILOBITES OF NORTH AMERICA, 



In which some new Genera and Species are proposed. By 



Jacob Green, M. D. Professor of Chemistry, &c. 



The following synopsis is only the precursor of a more ex- 

 tended work on this subject, and which is now nearly ready for 

 the press. All the species will be illustrated, by exact models, 

 in plaster of paris, instead of the usual drawings or representa- 

 tions on paper ; so that every copy of the book will be accom- 

 panied by a set of the casts. Naturalists being thus furnished 

 with fac similies of the objects described, will be enabled to cor- 

 rect, for themselves, any errors committed by the Author. 



Genus Calymene — Brongniart. 

 C. Blumenbachii — Brong. 



Clypeo rotunda to, tuberculis sex distinctis in fronte ; oculis in 

 genis eminentissimis ; corpore tuberculato. 

 C. Callicephala — Green. 



Clypeo antice attenuate, figura ilhformi in fronte depicta ; 

 oculis minimis ; abdomine quatuordecim articulis ; corpore 

 piano. 

 C. Selenecephala — Green. 



Clypeo antice rotundato ; margine omni valde incrassato ; 

 prominentia frontali utrinque trituberosa; corpore tuberculato. 

 C. Plutys— Gree/J. 



Clypeo antice rotundato — prominentia frontali utrinque qua- 

 tuor tuberculis ; articulis viginti duobus ; corpore expanso. 

 C. Microps — Green. 



Clypeo antice subattenuato ; oculis minimis in lateribus ca- 

 pitis; abdominis articulis a 14 ad 18 ; corpore depresso. 



