weeks. j PALEONTOLOGY, PETROLOGY, AND MINERALOGY, 1894. 77 
446 Penfield (S, L.). Mineralogieal notes. 
Am. Jour. Sci., 3d ser., vol. xlviii, pp. 114-118. 
Describes the crystallographic characters of octaliedrite from Arkan- 
sas, penfieldite, aud the cleavage and parting planes of orthoclase aud 
albite. 
440a Pentlandite. 
Abstract: Am. Nat., vol. xxviii, p. 519 (£p.). 
Noticed in Bibliograpby and Index for 1892 and 1893. 
447 and Howe (W. T. H.). On the cliemical composition of chon- 
drodite, hiimite, and clinokumite. 
Am. Jour. Sci., 3d ser., vol. xlvii, pp. 188-206. 
Abstracts: Am. Nat., vol. xxviii, pp. 872-873 (f p.); Am. Geol., vol. 
xiii, pp. 358-359 (J p.). 
Describes the crystallographie characters of chondrodite from War- 
saw and Brewster, N. Y. 
448 and Kreider (D. A.). Mineralogieal notes. 
Am. Jour. Sci., 3d ser., vol. xlviii, pp. 141-144. 
Discusses the identity of hydrofrahklinite and chalcophanite. 
440 and Minor (J. 0., jr.). On the chemical composition and 
related physical properties of topaz. 
Am. Jour. Sci., 3d ser., vol. xlvii, pp. 387-396. 
Abstract: Am. Geol., vol. xiii, p. 427 (10 1.). 
Gives a list of the localities from which the specimens examined 
were obtained and the chemical analyses of some of the specimens, 
discusses the related physical properties, and compares the charac- 
teristics of topaz and herderite. 
450 Penhallow (1>. P.). Note on inter-Glacial plants from the Don 
Valley [Ontario]. 
Am. Geol., vol. xiii, pp. 93-95. 
Describes Fraxinus quadrangulata Michx., Taxus baccata L. var. 
canadensis Gray, and Quercus obtusiloba Michx. 
451 Notes on Parian (Devonian) plants from New York and Penn- 
sylvania. 
U. S. Nat. Mus., Proc, vol. xvi, pp. 105-114, pis. ix-xiv. 
Describes and figures a number of new species found in Devonian 
strata at different localities of the States named. 
452 Penrose (B. A. F. ? jr.). The superficial alteration of ore deposits. 
Jour, of Geol., vol. ii, pp. 288-317. 
Discusses the relation of alteration in ore deposits and in country 
rocks, the agents, method, chemical and physical effects, and depth of 
alteration, and the characteristics of alteration in iron, manganese, 
copper, lead, zinc, gold, silver, and other metallic deposits. Describes 
the formation of haloid compounds in ore deposits in arid regions. 
453 Phillips (William B.). The phosphate rocks of Tennessee. 
Eng. and Mg. Jour., vol. lvii, p. 417. 
Describes the character of the phosphate rock of Hickman County, 
Tenn., and the lithologic character of the associated strata. Gives a 
typical vortical section of the beds, which are of Devonian age, and 
chemical analyses of the phosphate. 
