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nomic geology. Under the first head are given detailed accounts of 

 the topography, and also of the superficial accumulations, their nature, 

 and distribution. The sections on stratigraphic geology considers each 

 formation in succession, from the Salina to the Portage, giving the 

 local development and variations of each with fullness and precision. 

 Faunal characters are touched upon to some extent, no wide difference 

 in these respects from adjoining regions being noted. Under the head 

 of economic geology are considered all the rock products of the 

 county, their mode of exploitation, treatment, and economic value. 



3. The Principles of Paleontology. By Felix Bernard. Trans- 

 lated by C. E. Brooks, pp. 130-215. 



This paper is extracted from Bernard's Elements de Paleontologie, 

 Paris, 1895, and is translated and here published for the benefit of 

 American students to whom Bernard's entire works may not be accessi- 

 ble. No other writer has succeeded in setting ^forth so clearly the 

 actual condition of the science, its relations to other departments of 

 knowledge, and the inherent importance of the problems with which 

 it is wholly concerned. 



4. Development and Mode of Growth of Diplograptus, McCoy. By 



R. RUEDEMANN, pp. 2 I 7-258, Pis. I-V. 



The observations recorded in this paper are based upon material 

 in a remarkably perfect condition of preservation, obtained from the 

 Utica slate at Dolgeville, N. Y. The paper shows that these graptolites, 

 generally occurring as isolated stipes, were actually colonies composed 

 of a large number of such individual stipes, growing radially from a 

 center. The structure of the central part of the colony is shown to 

 consist in (i) a central floating sack or pneumatocyst, demonstrating 

 that the colony was unattached ; (2) a verticil of spherical gonangia, 

 within which are found masses of young graptolites or siculae attached 

 to a central axis; beneath the gonangia are (3) the radiately arranged 

 graptolite stipes attached by long, bare extensions of the axial rod or 

 virgula of each stipe. The paper is illustrated with five plates of 

 highly instructive drawings. 



5. A Revision of the Sponges and Ccelenterates of the Lower Helder- 

 berg Group of New York. By G. H. Girty, pp. 259-322, Pis. I-VII. 



In this paper the known species of the groups mentioned are rede- 

 scribed, with one new genus and ten new species. Four genera of 



