1094 EXPERIMENT STATION RECORD. 



thai they require annual treatment in order to secure a good crop of clean fruit. The 

 use of a dust spray considerably diminishes the cost and labor of spraying, but it is 

 quite inefficient. 



Trees sprayed with liquid Bordeaux mixture and Paris green retained their foliage 

 through the season, while the foliage turned yellow and fell off from the trees treated 

 with a dust mixture as readily as from the check trees. This loss of foliage is an 

 important matter in the growth of the tree and indicates clearly that the dust method 

 is not satisfactory. The dust spray is 52 per cent cheaper than the liquid spray but, 

 according to the author, has no other advantages. It is, therefore, recommended 

 that the orchardist spend his time and energy in perfecting his methods of prepara- 

 tion and application of Bordeaux mixtures combined with arsenicals. 



In these experiments the formula used for the liquid Bordeaux mixture was 4 lbs. 

 copper sulphate, 4 lbs. of lime, j lb. Paris green per 50 gal. of water, and a proprietary 

 form of Bordeaux and Paris green was used for the purpose of comparison. 



Spraying-, (i. F. Warren (New Jersey Stas. I!"/. 194, PP- SO).— The purpose of 

 the author was to combine in the present bulletin in a convenient form the various 

 recommendations which have been made by the station in previous publications 

 regarding the control of insects and fungus diseases. The bulletin constitutes a con- 

 venient summary of information on this subject and contains an account of the 

 purpose of spraying, the methods to be adopted in spraying various fruit and garden 

 crops, a spray calendar, formulas for the preparation of the more important fungicides 

 and insecticides, and a discussion of spray pumps. 



Spray calendar ( Vermont Sta. Spec. Bui, Apr., 1906, folio). — Formulas are given 

 for the preparation of lime-sulphur-salt wash, Paris green, Bordeaux mixture, Helle- 

 bore, and kerosene emulsion, and brief directions are given for the application of 

 these remedies. 



The preparation of emulsions of crude petroleum, T. M. Price ( U. S. Dept. 

 Agr., Bur. Anim. Indus. Circ. 89, pp. 4)- — The ordinary kerosene emulsion is not 

 well adapted for use as a dip or hand treatment for animals, since the oil does not 

 remain emulsified and is distributed unevenly on the surface of the body. 



Beaumont oil has been found by the Bureau to be an effective dip for destroying 

 cattle ticks. There are certain objections to its use, however, particularly an occa- 

 sional injury to cattle. Experiments were therefore made to secure an emulsion 

 which would remain uniform for an indefinite period. This was accomplished by 

 employing a formula calling for 2 gal. crude petroleum, 5 gal. water, and h lb. hard 

 soap. The soap is dissolved in hot water and the crude petroleum is added and 

 mixed with a spray pump, after which it is diluted with the desired amount of water. 



An emulsion of crude petroleum made in this way remains fluid indefinitely with- 

 out any tendency to a separation of oil and water. Brief directions are also given 

 for the preparation of emulsions and other oils. 



The fumigation of dwelling houses for vermin, C. Fuller (Natal Agr. Jour, 

 and Min. Bee, 8 (1905), Xo. 5, pp. 457-464, fig. 1) . — Directions are given for the use 

 of hydrocyanic-acid gas in destroying bedbugs, cockroaches, and other insects in 

 houses. For large rooms several generators may be arranged, and care should be 

 exercised to prevent one of them from being set in operation before the others if the 

 attendant is still in the room. It is recommended that the period of fumigation be 

 6 to 8 hours if possible, but never less than 3 hours. 



Key to the known larvae of the mosquitoes of the United States, H. G. Dyar 

 ( U. S. Dept. Agr., Bur. Ent. Circ. 72, pp. 6, fig. 1).— This circular contains an analyt- 

 ical key intended for use in the identification of the known larva? of mosquitoes. 



House flies, L. 0. Howard ( U. S. Dept. Agr., Bur. Ent. Circ. 71, pp. 9, figs. 9).— 

 This is a revision of Circular 35 (E. S. R., 10, p. 654). 



The distribution of tsetse flies in French East Africa and in Kongo, A. 

 Laveran (Compt. Rend. Acad. Sci. [Pans], 141 (1905), No. 23, pp. 929-932).— Brief 



