450 EXPERIMENT STATION RECORD. 



TLe couidia were found to retain their viability over winter, and, it is be- 

 lieved, probably their power to infect the host plant also. The author thinks 

 it doubtful whether the mycelium is perennial. Artificial inoculations show 

 some natural resistance by the host toward the fungus. The disease is said 

 to be limited by the age of the plants, as even with the most susceptible sorts 

 it was impossible to infect either the leaves or stems until they had attained a 

 certain growth and age. The time of natural infection is during May, and 

 spraying with fungicides containing copper should be made early in that month. 



Bordeaux mixture, S. Pickering {Gard. Chron., 3. ser., 42 (1907), JSlo. I07S, 

 p. 150). — In an editorial note an account is given of investigations on the 

 chemistry of Bordeaux mixture. 



It is stated that the claim that Bordeaux mixture consists principally of 

 copper hydroxid is not based upon fact, since it consists of 5 complex sub- 

 stances formed by the action of lime on copper sulphate, the particular one 

 depending on the proiiortious used. In making Bordeaux according to the 

 ordinary formula, where the weight of lime used is from 4 to G parts to every 

 G parts of crystallized copper sulphate, the substance formed is said to be a 

 double basic sulphate of copper and calcium. However, where the lime is re- 

 duced to the lowest proportions consistent with the precipitation of the whole 

 of the copper, the substance formed is essentially a basic sulphate of copper. In 

 the former case when the mixture is exposed to the air the basic calcium sul- 

 phate present will be attacked by carbon dioxid, and until the calcium suliihate 

 has all been converted into carbonate, the basic copper sulphate will remain 

 practically intact. Where the basic sulphate is present there will be no period 

 in which the fungicidal action is suspended, as there is no basic calcium sul- 

 phate present. This is held to be a decided advantage, as with the latter com- 

 pound for equal weights of copper taken, two and one-h^lf times as much copper 

 sulphate would be liberated as with the double basic compounds. 



For the preparation of the basic sulphate of copper, the author recommends 

 the use of limewater in the proportion of 107 pints of limewater to each p<>und 

 of copper sulphate. Bordeaux mixture made by this method is said to be more 

 efticient and cheaper than that made by the ordinary formula. It is claimed 

 that in all cases Bordeaux mixture should be tested in order to prevent the 

 scorching due to an excess of coi)per sulphate. 



ECONOMIC ZOOLOGY— ENTOMOLOGY. 



Game commissions and wardens; their appointment, powers, and duties, 

 R. W. Williams, Jr. (U. S. Dei)t. Agi:, Biol. Surrcu Bui. 28, pi). 285, pis. 8).— 

 This bulletin contains a general account of the oHice and duties of wardens, 

 a condensed summary of the provisions of game laws relating to enforcement 

 and the full text of such laws. The subject-matter is restricted to State laws. 

 The topics are elaborately discussed and the matter is arranged for ready 

 reference. 



Game laws for 1907, T. S. Palmer, H. Oldys, and C. E. Brewster .([/. S. 

 Dept. A(jr., Fanners' Bui, 308, pp. 52, figs. 4). — The essential new features 

 of game laws passed in 1907 are given. The close seasons for diffei*ent kinds 

 of game in the various States are shown iu a tabular form. The license 

 system for hunting and shipping game is also discussed. 



Our feathered immigrants, J. Drummond {Nciv Zeal. Dept. Agr., Dirs. Biol, 

 and Hort. Bui. 16, pp. VII -j- 49, pis. 8). — A circular letter of inquiry was 

 sent to the correspondents of the department regarding the economic relations 

 of introduced birds, a list of which was supplied. Considerable evidence was 



