ENTOMOLOGY. 995 



The K.-L. emulsions and spraying", ( '. P. Close i Delaware Sta. But. 73, pp. 

 The term "mixtures" for these insecticides is considered inappropriate and is 

 abandoned in favor of "emulsions." K.-L. emulsions were used quite extensively 

 during i In- pasl season with varj iir_ r results, from Buccess to a complete failure. 



The author examined into the cause of these failures and believes thai they were 

 due largely to an incomplete preparation of the insecticide and careless spraying. 

 It is recommended thai the mixture should in all cases be made by violent churning 

 and splashing l>y means <>i' a hoc or dasher. The mixture can qoI be made in large 

 lots by pumping or stirring. When nol properly prepared, K.-L. emulsions are 

 ineffective and to some extent dangerous. In some cases the grade of limoid used 

 was not quite up to tin- standard. It is claimed thai trees well Bprayed during the 

 previous fall remain quite free from San Jose* scale during June and July, after which 

 the insect begins to multiply. Two applications yearly are recommended for the 

 K.-L. emulsions, viz, in October <>r November, and again in late spring. In order 

 to increase the effectiveness of K.-L. emulsions tests were made of the combination 

 of various substances. 



A ,u r I combination was found by using sulphid of lime with the K.-L. emulsions. 



This gives a lime-sulphur combination \\ ith the addition of kerosene The author 

 reports good results from the use of K.-L. emulsions in strengths varying from \'2\ 

 to 30 per cent on peach, cherry, pear, and apple trees. Directions are also given for 

 the combination of Bordeaux mixture with K.-L. emulsions, and also forthe addi- 

 tion of Paris green to this mixture. It was found that K.-L. emulsion was a safe 

 and effective insecticide for dipping nursery stock. For use in the spring the author 

 recommends a 30 per cent strength on peach trees and :;"> per cent solution on other 

 t rees. 



Insects and insecticides ( Sacramento: State Hort. Com., 1905, pp. 23, figs. 

 The importance of careful and intelligent spraying is urged upon fruit growers. 

 Some of the more important fruit pests are described and recommendations made 

 regarding the best remedies for combating these insects. The more important pests 

 mentioned in this pamphlet include San Jose" scale, woolly aphis, prune aphis, Mack 

 peach aphis, hop louse, canker worms, tussock moth, grasshoppers, peach-tree borer, 

 peach moth, codling moth, etc. 



Annual report of the royal sericultural station, Padua i Ann. R. Staz. Bacol. 

 Padova,33 I 7906), pp. 119). — The work of the station, during the year L905, is reviewed 

 by the director, E. Verson (pp. 5-11). 



[n addition to a number of routine and practical matters the station studied the 

 regeneration of the appendages of the silkworm larvae, variations in the coloration 

 of cocoons in Lepidoptera, disinfection with corrosive sublimate and other antiseptics 

 in the case of flaccidity of silkworms, external markings indicating sex in silkworms, 

 physiological coloration of cocoons, and other subjects. A study of the weighl of 

 silkworm cocoons as related to sex was carried on by E. Verson (pp. 19-25). This 

 problem lias been studied for a number of years at the sericultural station, and the 

 conclusion is reached that the results thus far obtained indicate the impossibility of 

 depending upon any external marks in silkworm cocoons for determining the Bex. 



E. Quajat reports on the prolonged estivation of silkworm eggs pp.26 65 . These 



experiments were carried on with a number of races of silkworms, and in respect to 



the influence of heat the different races react quite differently. The green Japanese 

 race was found to he less resistant than the yellow .Japanese race or various hj brid 

 races or the native yellow race. On the whole, it is concluded that a temperature of 

 15 to 17° C. is most suitable for the preservation of silkworm eggs in the Bummer. 

 The same author presents an account of artificial parthenogenesis in silkworm eu r '_ r s 

 (pp. 77-92). In these experiments the author studied the influence of oxygen, high 

 temperature, sulphuric acid, hydrochloric acid, carbonic acid, and electricity upon 



