88 



SCIENCE 



[N. S. Vol. LII. No. 1334 



blowing sand. All degrees of reclamation by in- 

 vading vegetation are found. The types and char- 

 acteristics of the plants are noted and short lists 

 of the more important plants found at the various 

 stages are given. 



Notes on some Eocky Mountam plants, chiefly of 

 the Arapahoe mountains: L. H. Pammel and 

 E. I. Ckattt. 

 Further notes on the germination of some trees and 

 shrubs and their juvenile forms: L. H. Pammel 

 AND Charlotte M. King. 

 On the occurrence of the gi-ant puff hall: Hakrt 



M. Kellt. 

 The disintegration of certain intracellular bodies: 



Clifford H. Farr. 

 The teaching of plant pathology: W. H. Davis. 

 Plant tumors: Henry Albert. 

 The vegetation of Cape Blanco: Morton E. Peck. 

 The major vegetation of Lake Okoboji: Robert B. 



Wtlib. 

 Some Alaska fungi: J. P. Anderson. 

 The genus Ceanothus in Iowa: B. Shimek. 

 Querous lyrata Walter in Iowa: B. Shimek. 

 Seasonal variations in their relation to ecological 



field observations: B. Shimek. 

 Notes on the distribution of midsummer bee plants 

 im the Mississippi zone of Clayton county: Ada 

 Hatden. 

 The growth of foliage leaves: Beryl Taylor. 

 Comparison of the absorption occurring in corn 

 stalk tissue and in prepared bicolloids: L. E. 

 YocuM and a. L. Bakke. 

 Mechanical preparation of sweet corn pericarp: 



R. A. Rudnick and A. L. Bakke. 

 The OrchidaceoB of Nebraska: T. J. Fitzpatrick. 

 The influence of forest areas in non-forest regions 

 upon evaporation, soil moisture and movement 

 of ground water: I. Bode. 



The paper includes the results of a series of stud- 

 ies carried on in the northeastern part of Iowa dur- 

 ing the summer of 1919. The work covers a com- 

 parison of the evaporation and soil moisture 

 conditions obtaining on forested and non-forested 

 sites, and the influence that forested areas have 

 as to the checking of runoff, the absorption of 

 moisture in the soil and the response of various 

 soile at variious depths to precipitation. The re- 

 sults and conclusions bring out some very interest- 

 ing facts relative to the economic values of forest 

 areas of a state like Iowa in conserving soil mois- 



ture, checking evaporation and regulating the flow 

 of smaller streams throughout; the state. 



Chemistry 

 Simplifled electrotitration and its use in determin- 

 ing the iodine ion: W. S. Hendrixson. 

 An examination of rain and snow precipitations: 

 J. E. Trieschmann and Nicholas Knight. 

 The precipitations covering a period of 8J 

 months, from October 1, 1918, to June 15, 1919, 

 were examined. The samples were collected dn 

 granite pans 20 inches in diameter, on an open spot 

 near the center of the village of Mount Vernon, 

 Iowa. Tie nitrogen in the free and albuminoid 

 ammonia, nitrates and nitrites was determined. 

 Most of the winter precipitations contained sul- 

 phates, probably resulting from the combustion of 

 coal. A few analyses showed a trace of phosphate. 

 All the rain and snow contains a constant amount 

 of chlorine, probably carried in the winds from the 

 Atlantic. 

 An apparatus for determining solubilities up to 



the critical temperature: P. A. Bond. 

 The nitration of halogenated phenols: L. Charles 



Raipord. 

 Vacuum tube circuits as a source of power for con- 

 ductivity measurements : H. A. Geauqiie. 

 The free energy of dilution and the activity of the 

 ions of sodium bromide: J. N. Pearre and H. 

 B. Hart 



Geology 

 Iowa terranes compared with tlwse of adjoining 

 states: Charles Keybs. 



Since geologic phenomena are not restricted by 

 political boundaries many of the missing leaves of 

 Iowa's earth-history are found clearly imprinted in 

 contiguous states. But it is difficult to make very 

 close comparisons because of the diverse condi- 

 tions and the varied aims under which the terranal 

 schemes are constructed. By reducing to a stand- 

 ard the geological sections of our state and those 

 of surrounding states a classificatory plan is ef- 

 fected which, although perfectly elastic, permits 

 exact stratigraphic parallelism to be instituted. 

 Belated survival of Wernerian nomenclature: 

 Charles Keyes. 



Galena as denominating a notable Ordovicic dolo- 

 mite is not a geographic name, as is so often sup- 

 posed. James Hall, who proposed the term, de- 

 rived it directly from the chief mineral content of 

 the formation. In using the title thde author 

 manifestly modified Featherstonough 's earlier name 



