Geology and Natural History. 103 



gained by confusing on a geological map the distribution of fossil 

 faunas with the distribution of geological formations which the 

 map purports to represent. 



In the text accompanying the map the State geologist has con- 

 tributed an interesting and valuable detailed exhibit of the his- 

 torical development of the nomenclature of the New York State 

 geology. Among other things suggested by its examination is 

 the real significance and naturalness of the subdivisions proposed 

 by Mather in his report of 1840. The CatsMU, Helclerberg, 

 Ontario, and Chamijlain series express natural divisions of the 

 New York system, which is in great measure lost sight of in the 

 later attempts to adjust the classification to the European scheme. 

 As the details of our geology are developed, the grander episodes 

 in the sedimentation of each geological basin should be empha- 

 sized rather than warped to fit any universal scheme of classifica- 

 tion. A correct representation of the facts is far more important 

 than uniformity of classification or nomenclature. h. s. w. 



3. Geological Survey of Neio Jersey, Hexrt B. Kijmmel, 

 State Geologist ; Report on Paleontology, vol. iii. The Paleo- 

 zoic Faunas ; by Stuakt Weller, 462 pp., 53 pis. — Professor 

 Weller has presented a clear and concise account of a section of 

 the Paleozoic in the State next adjoining New York which pre- 

 sents many features quite distinct from that long-time standard. 



The sections fall into three quite distinct groupings in the three 

 areas of the Delaware Valley, Kittatinny Valley and Green Pond 

 Mountain region. In the first the Cambrian and Ordovician are 

 wanting — the Silurian and Devonian having full complement of 

 formations. The reverse is the case in the second area, and the 

 Ordovician and much of the Silurian and Devonian are missing 

 in the third. 



The Hardyston quartzite holds the Olenellus fauna. The Kit- 

 tatinny limestone, 2700 to 3000 feet in thickness, has a fauna 

 resembling the Upper Cambrian fauna of Minnesota and Wiscour 

 sin and in its upper part carries Ordovician species. The Trenton 

 limestone carries a Black River fauna below and pare Trenton 

 fauna above ; but not the highest fauna of the New York sec- 

 tion : it is 135 to 300 feet thick and runs up gradually into a 

 typical Hudson River slate. The Norman's Kill shale fauna 

 appears near the base of the Hudson River. The Shawangunk 

 conglomerate lies unconformably upon the latter, and reaches a 

 thickness of 1500 to 1600 feet. Above this is the Medina. (Long- 

 wood) sandstone, over 2300 feet thick. These are supposed to 

 represent the Oneida and Medina of New York, though no fossils 

 have been seen. Then follow, in the Delaware Valley, the Poxino 

 Island shale, the Bossardville limestone. Decker Ferry formation, 

 Rondout formation, and the Manlius limestone. The Decker 

 Ferry formation is correlated directly with the Coralline lime- 

 stone of New York. The Rondout contains almost exclusively 

 Leperditia, and Leperditia alia is in both it and the following 

 Manlius, which is the Spirifer vanuxemi zone. 



