Geology and Natural History. 419 



2. Federal Bureau of Mines ; Joseph A. Holmes, Director. 

 Bulletin I, The Volatile Matter of Coal ; by Horace C. Porter 

 and F, K. Ovitz. Pp. 56, with 20 tables and 9 figures.— This is the 

 first independent publication of the newly established Federal 

 Bureau of Mines (see v. xxx, p. 292). Tiie work here detailed is 

 now centered in the experiment station at Pittsburg, Penn., and 

 had its beginning in investigations carried on at the coal-testing 

 plant erected at St. Louis in 1904 in connection with the Louis- 

 ana Purchase Exposition. The authors state that " The investiga- 

 ion has already shown that the volatile content of different coals 

 differs greatly in character. The volatile matter of the younger 

 coals found in the West includes a large proportion of carbon 

 dioxide, carbon monoxide, and v^^ater, and a correspondingly 

 small proportion of hydrocarbons and tarry vapors. The older 

 bituminous coals of the Appalachian region yield volatile matter 

 containing large amounts of tarry vapors and hydrocarbons, difficult 

 to burn completely without considerable excess of air and a high 

 temperature. Coal of the western type, moreover, gives up its vol- 

 atile matter more easil y at moderate and low temperatures than that 

 of the other type. The volatile matter produced at medium and 

 low temperatures is rich in higher hydrocarbons of the methane 

 type, such as ethane and propane, which contain a larger portion 

 of carbon than is present in methane." The results are shown to 

 have important economic applications of interest to engineers and 

 mechanics in a variety of fields. Copies of the bulletin may be 

 obtained by applying to the Director of the Bureau of Mines at 

 Washington. 



3. Cambrian Geology and Paleontology No. 6 — Olenellus 

 and other Genera o/ «/ie Jfesonac2Wce / by Charles D. Walcott 

 (Smithsonian Miscel. Coll.), 53, 1910, pp. 231-422, pis, 23-44. — 

 Our knowledge of the large and diagnostic Lower Cambrian 

 trilobites is here greatly extended and made easily comprehensible 

 through an abundance of most excellent illustrations. Of these 

 trilobites there are in America and Europe 33 (16 new) species 

 distributed in the following genera : Nevadianew (1), Mesonaais 

 (2 Eui'opean, 1 American), Elliptocephala, (1), Gallavia (5 

 European, 2 American), Holmia (2 European, 1? American), 



Wanneria new (3), Pmdeumias new (1), Olenellus (3 European, 

 9 American), Peachella new (1), Olenelloides (1 European). All 

 of the genera (with one exception) common to America and 

 Europe are of the Atlantic realm. The exception is Holmia 

 rowei of the Cordilleran region, but it will very likely be shown 

 to belong to another genus related to Holmia. 



The stem genus and the oldest of the family is Nevadia, giving 

 rise in one line to Gallavia, Holmia, Wanneria, and in the 

 Middle Cambrian to Paradoxides. Another evoluted into the 

 remaining genera mentioned above, a branch that is not only the 

 most specialized but also has the most characteristic genera of the 

 family and of the Lower Cambrian. The evolution of this stock 

 as worked out by Walcott demonstrates that the telson of 



