64 EXPERIMENT STATION RECORD. 



mentioned. The objection is raised to the Webber and Swingle formula 

 that there is a large amount of sediment. Pure kerosene was used on 

 different trees without ill effects. The soil was mounded up at the 

 base of the young trees to prevent the oil collecting at that point. On 

 one large peach tree sprayed at least !>0 per cent of the scales were 

 killed. The remainder were protected by masses of leaves about the 

 limbs. Identical results were obtained in spraying Euonymus. The 

 experiments were performed when the trees were dormant. A manu- 

 facturing plant for kerosene emulsion in California is noted where 

 the emulsion is made at a cost of 13 cts. per gallon in the undiluted 

 state. When diluted the cost is a little over 1-i cts. per gallon. 



The lime, salt, and sulphur wash seems to be less effective in northern 

 California, where moist conditions prevail. Successful experiments are 

 noted with hydrocyanic-acid gas on trees on the grounds of the 

 Department of Agriculture. 



Experiments with formic aldehyde gas produced no results. It is not 

 worth considering in comparison with hydrocyanic-acid gas. 



The bean leaf beetle, F. H. Chittenden (pp. (54-71). — It is noted that 

 Cerotoma trifurcata has been found on beans in portions of Maryland 

 and Virginia, and it is thought probable that the species is on the 

 increase. A brief account of the literature is given, and of the insect's 

 occurrence in 1897. The insect in its different stages is described. Its 

 distribution is given from Canada southward to the Gulf States and 

 westward to Kansas and Minnesota. It has been found attacking tick 

 trefoil, hog peanuts, cowpeas, and beans. The beetles attack plants 

 somewhat differently, sometimes attacking the edges of the leaves, as 

 in the ease of the hog peanut, sometimes even consuming the mid-rib. 

 In the case of the bean and the eowpea they form large round holes in 

 the leaves. As they feed on the under surface of the leaves and are 

 at rest during the greater portion of the day they seldom attract 

 attention; but on wild plants they are found in the center of the upper 

 surface near the tops. The nature of their work is somewhat similar 

 to that of the grapevine colaspis. The eggs are laid around the stem 

 of the plant in clusters of from C to 10 and the larva', attack the plants 

 at this point. In Minnesota, the first generation is said to feed on beans 

 and the second on cowpeas. In the District of Columbia it is thought 

 that the period of egg deposition extends from the middle of May 

 through June, and that the entire life cycle probably requires six to 

 nine weeks. Spraying with arsenicals and clean culture are advised. 



Notes on Anarsia lineatella, A. B. Cordley (pp 71-75). — The work of 

 this insect in Oregon on peach and prune trees and strawberry plants 

 is discussed. It is thought that two species must be involved in the 

 description of Anarsia lineatella, or else a dimorphism due to food plants 

 and seasons exists. One of the species it is thought feeds normally on 

 strawberry plants, the other upon trees of the genus Primus. It is 

 thought that possibly one may be Anarsia primus. 



