June 25, 1915] 



SCIENCE 



949 



typically arid transition. There follows an an- 

 notated list of plants recorded by the writer on a 

 trip across the arid transition in this section of the 

 state in July, 1914. 



Flora of the Bacing Biver Begion: Hakriette S. 



Kellogg. 



In August, 1914, the writer collected plants 

 along the south bank of the Rainy River near the 

 "Old Dock'' in the city of International Falls, 

 Minnesota. 



The territory explored consisted of a timber 

 belt lying back from the river and cleared ground 

 still back of this. 



The timbered belt consisted largely of birches, 

 poplars, maples and other deciduous trees inter- 

 spersed with cedars and spruces and species of an 

 arborescent nature. Underneath was the charac- 

 teristic forest herb flora; the cleared ground was 

 covered with introduced plants of a weedy char- 

 acter; there was an almost entire absence of 

 strand flora. East of the dock was a luxuriant 

 growth of tame grasses and clovers, the seed of 

 which had been scattered when grain was carried 

 to the dock for transportation by boat. 



A few species are listed that were collected from 

 the Canadian bank of the river, several from the 

 Rainy Lake region and a few from the west bank 

 of the Winnipeg River. 



Economic Seaweeds of Alaska (illustrated) : Rob- 

 ert B. Wylee. 



A brief statement of the findings of the U. S. 

 Kelp Expedition which made a survey of the pot- 

 ash-yielding seaweeds of southeastern Alaska dur- 

 ing the summer of 1913. 



A Hyirid Bagweed (illustrated) : Robert B. 



Wylie. 



The description of a hybrid, probably a cross 

 between Ambrosia artemisiifolia and A. trifida, 

 found near Iowa City during the summer of 1914. 



The Distribution of Forest and Prairie in the 

 Lake Begion of Iowa (with lantern slides) : B. 

 Shimek. 



The Okoboji region is discussed. The groves 

 appear uniformly on, or in the shelter of abrupt 

 slopes or in rough areas consisting of a group of 

 ridges or knobs. They are found on the leeward 

 side of abrupt slopes anywhere about the lakes; 

 but they occur on the vrindward side only on the 

 east and north sides of the larger lakes. In the 

 latter case the establishment of a forest seems to 

 be made possible by the piling up of vapors under 

 the banks on the windward side. 



The Lichen Flora of the Prairies of Northwestern 



Iowa: B. Shimek. 



This consists largely of xerophytie species at- 

 tached to boulders. Few earth forms occur. The 

 rock forms are most abundant on dry knolls and 

 in exposed places. A comparison of this flora is 

 made with that of the xerophytie borders of 

 prairie burr oak groves. An annotated list of the 

 species is included. 



The Ecological Histology of Certain Prairie 



Plants: Ella Shimek. 



The paper discusses the xerophytie adaptation 

 of certain species of prairie plants in detail. 



Pioneer Plants on a New Levee: Frank E. A. 



Thone. 



A description of the plants appearing on a 

 newly exposed surface in Des Moines, Iowa, dur- 

 ing the first season after exposure, with remarks 

 concerning their possible origin. 

 The Index of Foliar Transforming Power as an 



Indicator of Permanent Wilting of Plants: A. L. 



Bakke. 

 Some Well-known Building Stones: Nicholas 



Knight. 



An analysis was made of the Anston Stone, 

 from Kiveton Park, England, the material of 

 which the Houses of Parliament are built, to learn, 

 if possible, the cause of the crumbling of the 

 rock. It proved to be a dolomite, of a light bufE 

 color, with a specific gravity of 2.6. 



The red sandstone from the Vosges Mountains, 

 of which many public and private buildings in 

 Alsace-Lorraine, including the Strassburg Cathe- 

 dral, are constructed, was studied. The rock is a 

 hard, durable building material and lends itself to 

 delicate carvings, as shown, by the fine Gothic of 

 the tower and facade of the cathedral. 



The "Hard Jewish," a compact rock from Sol- 

 omon's quarries, Jerusalem, with a specific gravity 

 of 2.7, also was analyzed. 



A New Apparatus for Begulating Temperatures 

 for Work in Polarimetry and Befractivity; Elec- 

 trical Conductivity of Solutions of Silver Nitrate 

 in Water and Pyridine and in their Binary Mix- 

 tures (preliminary paper) : J. N. Peabce. 



A Convenient Standard Cell — (Cu — Hg) — CuSOi 

 — Hg.SOi — Hg: Dieti Ung Huong and J. N. 

 Pearce. 



Some Derivatives of i-nitro-5-methyl-2-sulphoben- 

 zoic Acid: "Wm. J. Karslake and P. A. Bond. 



Comparison of Some Standards in Aoidimetry and 

 Alkalimetry : W. S. Hendrixson. 



