FIELD CROPS. 327 



plants. Fruit setting is taken as the basis for determining the vitality of the 

 pollen. 



The experiments have run a number of years, and with apples no definite 

 relation was found between the age of the pollen and successful pollination. 

 The percentage of success following the transfer of pollen which varied from 

 fresh to 11 days old ranged from where the fresh pollen was transferred to 

 the flowers to 32 per cent where pollen 11 days ©Id was used. The average of 

 all tests gave 17.62 per cent setting of fruit. 



With strawberries the percentage of successfu. pollinations varied from 52.5 

 in 1912 to 84 in 1909. With fresh pollen 59 per cent of the pollirations were 

 successful, while 61.5 per cent was attained where the pollen was 4 days old. 



With sweet peas summer and winter pollinations were undertaken, in all 

 11,393 pollinations having been made. The averages of the summer and winter 

 pollinations that successfully set fruit showed but little difference, the range 

 being from 33 to 46 per cent. • 



From the experiments reported it is stated that the maximum age at which 

 pollen was successfully used was for the apple 11 days, for the strawberiy 15 

 days and 17 hours, and for the sweet pea 6 days in summer and 22 days and 

 22 hours In winter. 



Directions for collecting plants, P. I. Rickeb (U. 8. Dept. Agr., Bur. Plant 

 Indm. arc. 126, pp. 21-35, figs. 5).— The author describes the various imple- 

 ments needed in the cellection of plants and gives special directions for their 

 preparation and drying. 



International catalogue of scientific literature. M— Botany {Internat. Cat. 

 Sci. Lit., 10 (1913), PP- VII I +S.'fO).— This is in continuation of the series pre- 

 viously noted (B. S. R., 27, p. 31) and lists more than 7,300 titles of articles on 

 botany, most of which appeared during 1910 and 1911. The American literature 

 seems more adequately treated than in previous numbers. 



EIELD CKOPS. 



Influence of vaxious fertilizer salts on the germination of field crop seeds, 

 A. RuscHE {Jour. Landw., GO {1912), No. 4, PP- 305-365) .—Twenty-four kinds 

 of fertilizer salts, including chlorids, nitrates, sulphates, carbonates, and phos- 

 phates, were tested at the rate of 10 gm. per pot (containing 11.5 kg. of soil), 

 with barley, beans, beets, alsike clover, red clover, white clover, blue lucern, 

 blue lupines, oats, peas, rape, rye, serradella, and wheat. Numerous tables 

 show the results of seed germination, length of root, weights of above-ground 

 and underground parts, ratio of root weight to remainder of plant, and relation 

 of root length to weight. The water capacity of the soil was maintained at 



70 per cent. 



The influence of the various salts upon germination was as follows: Potas- 

 sium chlorid did not produce an unfavorable influence on the germinating 

 ability of the cereals, peas, kidney beans, rape, or beets, but the energy of 

 germination was somewhat suppressed. With the clovers, serradella. alfalfa, 

 and lupines this salt worked unfavorably. Sodium chlorid, except with barley, 

 lupines, serradella, and rape, also worked unfavorably, being especially harmful 

 to white clover, red clover, alsike clover, and alfalfa, but was particularly 

 advantageous on lupines. Magnesium chlorid produced, in general, effects 

 similar to potassium chlorid, although the germination figures were a little 

 higher with alfalfa, red and white clover, and serradella, and considerably 

 lower with lupines. Calcium chlorid also had a similar effect to potassium 

 chlorid, except with beets, which showed fewer germinations than with potas- 

 sium chlorid. In comparison with magnesium chlorid, calcium chlorid gave a 



