November 29, 1901.] 



SCIENCE. 



849 



is a ' black body ' toward sound waves, is not 

 sufficient to explain this difference. 



Ernest Merritt. 



biological society of washington. 



The 342d meeting was held on Saturday even- 

 ning, November 2. 



Mr. H. J. Webber exhibited specimens of the 

 pineapple suffering from the disease termed 'root 

 bind. ' This was caused by planting improperly 

 trimmed cuttings, which caused the roots as 

 they developed to wind tightly around the stalk, 

 causing defective nutrition and finally death. 



Charles Louis Pollard gave some ' Notes on a 

 Trip to Mount Mitchell,' made during the pres- 

 ent spring for the purpose of obtaining botan- 

 ical specimens and of studying incidentally the 

 distribution of certain species of violets. 



H. J. Webber described ' A Cow Pea Re- 

 sistant to Root Knot Worm,' stating that in ex- 

 amining an extensive series of cow peas and 

 other plants this one variety had been found 

 entirely free from the parasites, although grow- 

 ing immediately between two varieties that 

 were badly affected. The root knot worm, a 

 small nematode, not only affected cow peas, 

 but very many plants, doing serious damage, 

 and the finding of the cow pea led to the hope 

 that other plants might be found equally re- 

 sistant, while by planting the pea as an alter- 

 nating crop it would be possible to lessen the 

 numbers of the worms. 



Frederick V. Coville gave an ' Exhibition of 

 Specimens of Alaskan Willows,' including ex- 

 amples of all species from that region. For 

 descriptive purposes the speaker grouped these 

 willows in three divisions, the tree, bush and 

 procumbent forms, exhibiting a series of slides 

 showing the floral divisions of Alaska and illus- 

 trating the habitat of the various groups. The 

 different species were described in some detail 

 as to their range, abundance or rarity, date 

 of discovery and economic value when the spe- 

 cies was of sufficient size. 



M. A. Carleton spoke of the 'Characteristics 

 and Distribution of Xerophytic Wheats,' illus- 

 trating his remarks with lantern slides of the 

 Russian wheat region. The speaker said that 

 wheats were grouped in eight divisions : (1) 

 Common ; (2) Club or square head ; (3) Poulard ; 



(4) Durum or macaroni ; (5) Polish ; (6) Spelt ; 

 (7) Emmer; (8) Eiukorn. 



What might be called xerophytic or drought- 

 resistant wheats belong to several of these 

 groups, but the most important ones belong in 

 the durum or macaroni wheat group. This is 

 the group, therefore, which was chiefly dis- 

 cussed. These wheats differ from the ordinary 

 wheats as now known in this country by having 

 rather large flattened heads with large chaff 

 and very large yellowish white grains which 

 are extremely hard and vitreous in fracture, and 

 often rather transparent. They always have 

 beards, which are usually very long. In some 

 varieties the heads and beards are black. These 

 wheats are very resistant to drought, being able 

 to grow where the rainfall is as low as ten inches 

 per annum. They also resist the leaf rust very 

 greatly, but are more or less subject to stem 

 rust when it occurs in very great abundance. 

 They are also seldom injured by bunt, smut or 

 other diseases. Naturally they are adapted to 

 semi-arid or arid regions, and at present are 

 growing mainly in east and south Russia, Al- 

 geria, Argentina, parts of India and in various 

 portions of the Orient and Mediterranean re- 

 gion. In this country they are especially 

 adapted to our semi-arid plains from North 

 Dakota to Texas. 



The investigations of this department on the 

 basis of soil and climate have led us to believe 

 that those wheats will yield about one-third 

 more to the acre in our semi-arid regions than 

 other wheats, and what is more important, pro- 

 duce a constant yearly crop in large portions of 

 that region where other wheat cannot be grown 

 at all. Numerous practical tests have since 

 proved this prediction to be justified. At the 

 same time these wheats are the very best 

 adapted for making macaroni, and there is now 

 a great demand for them from this country, the 

 people in Europe having learned of what good 

 quality they are. Wherever they have been 

 tried for the purpose, they also are considered 

 to make excellent bread. In the establishment 

 of these durum wheats we have a striking ex- 

 ample of the beneficial results that may follow 

 purely scientific investigations. 



T. W. Stanton, 



Secretary. 



