DISEASES OF PLANTS. 9fi7 



ranked first, American red second, Canadian third, the others greatly 

 inferior, and the French nothing. 



The general conclusion is drawn that the product depends on the 

 germinating power of the seed used and the number of pure and ger- 

 minating seed per pound. If these conditions are satisfied the size 

 and appearance of seed will be of little account. As a satisfactory 

 basis for valuation of seed the author states that the purchaser should 

 take into account the percentage of purity, percentage of germination, 

 and number of seeds per pound. The highest priced seed in his experi- 

 ence did not yield the largest crop. 



Studies in germination, V. Jodin (Ann. Agron., 24 (1898), No. 8, 

 pp. 382-397). — The author continues to report his investigations on the 

 germination of seed, the present paper treating of the differences 

 between very old and fresh seed in their intramolecular respiration and 

 on the potentiality of seed. Intramolecular respiration was found to 

 diminish as the age of seed increased. Peas 33 years old failed to give 

 off carbon dioxid when in suitable media for germination. A very 

 small quantity was given off from 27-year-old peas and increasing 

 amounts from still newer seed. 



Influence of the weight of seed on the yield of cereals, L. Grandeau (Jour. 

 Soc. Agr. Brabant- Hainaut, 189S, No. 47). 



Tobacco seed: its choice; light and heavy seed, Trabut (Gouv. Algerie Bot. 

 Service BuL, 189S, No. 17, pp. 8. ill us. ). 



On the specific gravity of rice seeds at different stages of ripening, H. Axdo 

 (Imp. Univ. Col. Agr. [Tokyo] Bui., Vol. 3, No. 5, pp. 479-481). — The specific gravity of 

 rice seed was tested at various periods of growth, namely, milk-ripe, green-ripe, 

 yellow-ripe, full-ripe, and dead-ripe. From the tables given it is clearly shown that 

 the specific gravity increases with ripening. 



DISEASES OF PLANTS. 



On the use of sulphur and sulphate of ammonia as preventives 

 of potato scab in contaminated soils, H. J. Wheeler and G. E. 

 Adams (Rhode Island Sta. Rpt. 1897, pp. 254-268).— -The trials with 

 sulphur which were conducted in 1896 (E. S. R., 8, p. 798) indicated 

 that when thoroughly mixed at the rate of 600 lbs. per acre in the 

 upper 7 or 8 in. of a badly contaminated soil, though checking the 

 diseases somewhat, was practically useless. In 1897 2 series of experi- 

 ments were made to continue the study. 



In the first series seed tubers of the variety New Queen, which were 

 practically free from scab, were planted in pots 26 in. deep and 18 in. 

 in diameter, which were buried in the ground to within 2 in. of their 

 tops. Each pot received as fertilizer air-slaked lime, dried blood, 

 nitrate of soda, muriate of potash, dissolved boneblack, and tankage. 

 In previous years the pots had received barnyard manure alone or with 

 common salt, sodium carbonate, or oxalic acid. Sulphur and corrosive 

 sublimate were compared as fungicides. Part of the tubers were 

 treated with 1:1,000 corrosive sublimate solution for 1£ hours; others 



