abstracts: paleontology 371 



GEOLOGY. — Raritan, New Jersey, folio. W. S. Bayley, R. D. Salis- 

 bury, and H. B. Kummel. Geologic Atlas of the United States, 

 No. 191; U. S. Geological Survey. Pp. 32, with sections and 5 

 maps. 1914. 



The area treated is in the center of the Highlands of New Jersey and 

 contains some of the most important magnetite mines of the State. The 

 out-cropping hard rocks embrace pre-Cambrian, Cambrian, Ordovician, 

 Silurian, Devonian, and Triassic sediments, pre-Cambrian and Triassic 

 igneous rocks, and metamorphic pre-Cambrian rocks of undetermined 

 origin. Above these are unconsolidated deposits of Quaternarj^ age. 



The pre-Cambrian rocks lie in a series of northeast trending 

 ridges, between which are valleys underlain by Paleozoic beds. These 

 ridges and the intervening valleys constitute the Highlands. The north- 

 west corner of the quadrangle includes a small area of the Kittatinny 

 Valley which borders the Highlands on the north. This is underlain by 

 Cambrian and Ordovician rocks. On the south the Highlands are 

 bordered by the Piedmont plateau which in this area is underlain by 

 Triassic sedimentary formations and associated basalt flows and diabase 

 sheets and dikes. 



The Quaternary deposits include glacial material of the Jerseyan and 

 Wisconsin stages, old and recent alluvium and deposits of the glacial 

 Lake Passaic. The terminal moraine of the Wisconsin stage crosses the 

 quadrangle in an east-west direction about six miles from its northside. 



The principal economic resources of the quadrangle are magnetic 

 and limonitic iron ores, building stone, crushed rock, and lime rock. Of 

 less importance are claj^, sand, gravel, peat, and roofing slate. The 

 water resources are valuable as water supplies and for the development 

 of power. The magnetite, which is by far the most valuable economic 

 product, is regarded as of magmatic origin. The iron is believed to have 

 been contributed by the same magma that formed also the granitoid 

 gneisses and pegmatites that constitute the greater part of the pre- 

 Cambrian rocks. Brief descriptions of the principal mines in the area 

 illustrate the manner of occurrence of the ore. W. S. B. 



PALEONTOLOGY.— Caw6nan Geology and Paleontology, II. No. 11.— 

 New Lower Cambrian suhfauna. Charles D. Walcott. Smith- 

 sonian Miscellaneous Collestions ST^i : 309-326, pis. 50-54. July 21, 

 1913. 

 In this paper is described a hitherto unrecognized Lower Cambrian 



subfauna. It occurs in the Mahto formation (upper portion of the 



