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not previously been done. The permeability tests demonstrate that 

 sand when moistened and rammed into a mold is usually from two to 

 ten times as permeable as the same sand in a dry, disintegrated state, 

 which shows the extent to which granulation is effective. The permeabil- 

 ity tests serve also to emphasize what was inferred in advance, that the 

 porosity of a sand in its natural state is no measure of, and not necessarily 

 an index to the permeability, either in the natural state or after being 

 molded. The permeability of the molded sand is a function of the struc- 

 ture developed, which in turn is largely a matter of granulation. 



When the field work was done for this Bulletin in 1918, foundry 

 sands and clays were being shipped in large quantities from distant 

 localities in New York, Missouri, Illinois, Ohio, Kentucky, and Colorado. 

 As a result of this investigation nearly all of the materials that were 

 required in the foundries were found to occur in Minnesota. 



Contributions to the Paleobotany of Peru, Bolivia and Chile. Five 

 papers by Edward W. Berry. ''The Johns Hopkins Univer- 

 sity Studies in Geology," No. 4. Baltimore, 1922. Pp. 221, 

 pis. 25, figs. 9. 



The following five topics are treated in these papers: " Carboniferous 

 Plants from Peru"; "The Mesozoic Flora of Peru"; "The Flora of 

 the Concepcion-Arauco Coal Measures of Chile"; "Pliocene Fossil 

 Plants from Eastern Bolivia"; "Late Tertiary Plants from Jancocata, 

 Bolivia." 



In his first paper. Berry examines the coal-bearing rocks south of 

 the Port of Pisco on the peninsula of Paracas, which is about 220 km. 

 south of Callao. He thinks that these deposits correspond to the West- 

 phahan stage. His conclusions are based largely upon the fossil plants 

 found in these deposits. The following genera are represented by rather 

 common species: Palmatopteris, Eremopteris, Calamites, Calamo- 

 stachys, Lepidodendron, Lepidophyllum, Lepidostrobus, Stigmaria, and 

 Knorria. 



Berry's second paper in this collection attempts to sum up our 

 present knowledge of the Peruvian Mesozoic flora. Mesozoic rocks are 

 very widespread in Peru, and are particularly prominent in the Cordil- 

 lera Occidental, especially between latitudes 5° and 13° S. Most of 

 the Jurassic and Cretaceous horizons are represented. A collection of 

 fossil plants was made on the San Lorenzo Island. Berry gives a 

 list of genera from the Mesozoic of Peru, all of which, with one excep- 



