Geology and Natural History. 295 



and figuring other undetermined species of each of these genera 

 except Paradoxides and of Anomocare ; and from the upper beds, 

 2 species of Anomocare, 1 of Platypeltis and 1 of Psilocephalus, 

 besides undetermined species of Conocoryphe and Liostracus. 

 All are new species. 



4. A Bibliography of the Foraminifera, Recent and Fossil, 

 from 1565 to 1888, with notes explanatory of some of the rare 

 and little known publications; by Charles Davis Sherburn, 

 F.G-.S. 152 pp. 8vo. London, 1888. (Dulau & Co., Soho Square). 

 — Mr. Sherborn's Bibliography has been prepared evidently with 

 great care and thoroughness. A letter of his published in Nature 

 for April 19th states that he was prompted to prepare the work 

 by the imperfections in the bibliography published by the Minne- 

 sota Natural History Survey. 



5. Decomposition of Native Iron Sulphides. — Prof. A. A. 

 Julien has investigated with much care (Ann. N. Y. Acad. Sci., 

 iv, 1888) the minerals pyrite, marcasite and pyrrhotite with refer- 

 ence to their decomposibility in order to ascertain the cause of 

 the difference in durability of some of the kinds of so-called 

 pyrites. He reaches the conclusion that pyrite usually contains 

 more or less marcasite, and as marcasite is the more oxidizable 

 sulphide, the more marcasite present the more ready it is to oxidize. 

 Pyrrhotite may be present in pyrite with the same result, but 

 this is not common. The mixture of marcasite and pyrite, he 

 observes, may be due either to mixture during crystallization* or 

 to alteration, and the alteration may go so far as to produce a 

 paramorph. A light color in pyrite shading toward white, or 

 specific gravity below 4*99 is evidence that marcasite is probably 

 present, even when the pyrite is well crystallized ; but " little dan- 

 ger from decomposition may be expected down to a specific grav- 

 ity 4*97, equivalent to at least 80 per cent of pyrite." 



6. Rock-Forming Minerals ; by Frank Rutley, F.G.S. 252 

 pp. 8vo. Londqn, 1888 (Thomas Murby). — This is a useful book, 

 giving in systematic form and with considerable fullness, the meth- 

 ods of petrographical research and particularly the characters of 

 the minerals which enter into the composition of rocks. There is 

 no lack of books of this character, but for the most part they are 

 in German, and the English-speaking student has been thus at a 

 disadvantage ; this new work will consequently find a welcome at 

 once. 



7. Uraninite (Communicated). — Dr. W. F. Hillebrand, who 

 has been working for some time past on the composition of 

 uraninite, states that he finds in the Middletown mineral 10 per 

 cent of Th0 2 , in that from Branchville 7 per cent, and in that from 

 Colorado, 7 per cent of Zr0 2 without Th0 2 . The detailed dis- 

 cussion of the subject will be published later. 



8. Heather in Townsend, Mass. — M rs. Ralph Ball, of Town- 

 send Centre, Middlesex County, reported, this summer, a new 

 station for Calluna vulgaris. The locality, which is only a few 

 miles from the New Hampshire line, has just been visited by Dr. 



