BEPOKT OF NATIONAL MUSEUM, 1915, 65 



Gregory, of the American Museum of Natural History; and Prof. 

 W. B. Scott, of Princeton University. 



Paleobotany. — A somewhat fragmental and distorted stump from 

 the Stanley Mine at Sykesville, Pa., fairly satisfactory as an exhibi- 

 tion specimen, was the only addition, worthy of mention, received by 

 this section. The collection of fossil plants is undergoing rear- 

 rangement under the three great geological divisions. Paleozoic, Me- 

 sozoic and Cenozoic, the intention being to build up a stratigrax^hic 

 series representing the floras of all the different geological localities, 

 and a biologic series illustrating classification, and containing the 

 type specimens. This work is being carried on under the supervi- 

 sion of Dr. David White, associate curator of paleobotany, and Dr. 

 F. H. Knowlton, custodian of Mesozoic plants. 



Dr. Knowlton completed a monograph on the Laramie flora of 

 North America, a work which he has had in progress for some years. 

 Dr. G. E. Wieland, of Yale University, devoted considerable time to 

 the study of the fossil cycads, and Dr. Arthur Hollick, of the New 

 York Botanical Garden, to the Cretaceous and Tertiary floras of 

 Alaska. Dr. E. W. Berry, of Johns Hopkins University, also made 

 extensive use of the collections. 



Exhibition collections. — Aside from the occasional insertion of new 

 material in the exhibition series already established, the principal 

 changes in the exhibition halls were as follows: In systematic geol- 

 ogy two cases illustrating the characteristic rock and mineral associa- 

 tions of the pegmatites of the eastern United States were installed. 

 In economic geology two heavy granite posts of Minnesota marble, a 

 column of coralline marble from England, and 10 large slabs of na- 

 tive and foreign marbles were added to the building-stone collection. 

 The ore series was increased by one large mass of nickeliferous 

 pyrrhotite with silicate inclosure, from the Gap Mine, at Lancaster, 

 Pa.; two fine samples of Japanese copper ore weighing upward of 

 200 pounds each ; an unusually fine series of tungsten and vanadium 

 ores; a case devoted to illustrations of the genesis of iron ores; and 

 two cases illustrating the occurrence and mineral association of the 

 zinc ores of Sussex County, N. J., and southwestern Missouri. 



In the mineral hall seven new flat-top cases were introduced, two 

 of which are devoted to recent accessions, one to newly described 

 minerals, two to the Shepard collection of minerals, one to models 

 of gems of historical interest and artificial gems, and one to gem 

 minerals in the rough with stones cut from the same. 



The exhibit of fossil invertebrates was enlarged by one upright 

 case of crinoids representing the fauna of the upper Mississippian 

 formations, a flat-top case of sponges, and two American and one flat- 

 top case in which are illustrated the evolution and classification of the 

 12264°— NAT Mus 1915 5 



