187 



Other measures include the use of pyrethrum and sodium fluoride. 

 These substances are decidedly repellent to ants and quickly cause 

 death when they come in contact with the bodies of the insects, but 

 their strength is lost on exposure to air and wet weather. Pyrethrum 

 is also effective in freeing trees of ants after banding. The success 

 of shelter traps [R. A.E., A, vi, 313] depends on rainy weather. The 

 winter of 1917-18 in California was mild, and the ants were active 

 throughout the season ; but even under ideal conditions this method 

 is less effective and more expensive than the use of poisoned syrups. 



Arsenic in some form is the best poison for this purpose, although 

 some non-arsenicals have been used. Watertight cans set in the 

 ground along the main runways of the ants are useful ground traps. 

 Arsenical sj-rups are not attractive in the hot summer months, when 

 the ants are very active. They have been observed moving freely 

 at a temperature of 117° F., but they become sluggish at 50° F., and 

 it is then that the syrup is most effective. During the blossoming 

 period ants are attracted to the nectar, and control is difficult. Excel- 

 lent results in complete eradication have been obtained in orchards 

 heavily infested with scales by following up the usual autumn fumigation 

 with ant control. The authors recommend that control be started 

 between the time the ants first appear in the spring and the beginning 

 of July, or from the end of September until congregation into winter 

 colonies takes place. Clean culture should be practised in orchards, 

 and the lower branches pruned wherever possible, to prevent access 

 to the trees except by the trunk. 



It is said that this species will not tolerate the presence of other 

 ants, of which the commonest in Calif ornian citrus groves that are not 

 overrun with /. humilis include : Prenolepis imparts, Say, Formica 

 cinerea, Mayr, var. pilicornis, Emery, Tapinoma sessile, Say, Dory- 

 myrniex pyramicus, Roger, and Cremastogaster lineolata. Say, var. 

 californica, Emery. 



MiLLiKEN ^F. B.). Results of Work on Blister Beetles in Kansas. — 



U.S. Dept. Agric, Washington, D.C., Bull. 967, 14th October 

 1921, 26 pp., 22 figs., 3 tables. [Received 6th February 1922.] 



Blister beetles are of much less value than formerly and must be 

 considered injurious, and they will become more so with continued 

 agricultural development of semi-arid areas. They devour the petals 

 and pollen of flowers of beans, peanuts, locust trees and lucerne, but 

 on potatoes, sugar-beet and, to a lesser extent, on Russian olives they 

 commonly defoliate the plant. In either case the actual injury to the 

 crop depends on the stage of growth ; as the plants near maturity, 

 the yield is lessened, but the crop is not a total loss. Defoliation 

 of potatoes and the destruction of beans and peanut blossoms are 

 usually disastrous. A list is given of the food-plants attacked. 



A key is given to the species of Epicauta and Macrobasis collected 

 in Kansas. Eggs of M. immaculata are deposited in small cavities 

 in the soil wherever the female may be feeding. They hatch in about 

 12 to 14 days, and the active triungulin larvae at once search for 

 grasshopper egg-capsules. The coarctate larvae hibernate during the 

 winter, and they may be found late in summer or spring. Pupation 

 occurs in May, and this stages averages about 18 days. The life- 

 history of Epicauta maculata is practically identical with that of M. 

 immacidaia. Coarctate larvae of E. cinerea occur at all seasons 



(5980) N 2 



