254 EXPERIMENT STATION EECORD. 



keepers aud hiA-es, and the amount and value of comb and honey produced in 

 the A'arious sections of Tunis. 



The chalcidoid parasites of the coccid Kermes pubescens, with, descriptions 

 of two new genera and three new species of Encyrtinae from Illinois, A. A. 

 GiEATJLT (Canad. Ent., 43 (1911), No. 5, pp. 16S-178). — Cristafithorax ptilcher 

 and JEnasioidea latiscapus, representing new genera and species, and Microterys 

 speciosissimus n. sp. are recorded as reared from K. puliescens on oak at Ur- 

 bana, III. 



Notes on the breeding of Tropidopria conica, G. E. Sanders {Canad. Ent., 

 IfS (1911), No. 2, pp. .',8-50, fig. 1). — About 40 per cent of the puparia of Eristalis 

 tcnax, collected under natural conditions at Ottawa in August and September, 

 1910, was found to be parasitized by the proctotrypid T. conica. The largest 

 number of adults bred from a puparium was 46, the lowest 21, with an average 

 of 35. 



Field work in the control of the Argentine ant, L. J. Nickels (Jour. Econ. 

 Ent., 4 (1911), No. Jf, pp. 353-358). — Control operations carried on at Berkeley, 

 Cal., where 2 small, isolated colonies of Argentine ants have become established, 

 are described. The results obtained have been very satisfactory thus far, it 

 having been found possible to exterminate this pest and to prevent absolutely 

 its spread. 



Notes on a sawfly injurious to ash, E. R. Sassceb (Proc. Ent. Soc. Wash., 

 13 (1911), No. 2, j)p. 107, 108, pi. 1). — Notes on the life history and bionomics 

 of Tomostethus multicinctus, which for several seasons has defoliated white 

 ash in certain sections of Washington, D. C, are presented. Observations for 

 4 successive years show this sawfly to be single brooded. 



A new enemy of the mulberry tree (ViUaggio, 36 (1911), No. 1822, p. 254; 

 abs. in Internat. Inst. Ayr. [Rornc^, Bui. Bur. Agr. Intel, and Plant Diseases, 2 

 (1911), No. 5, p. 1194). — The red spider Tetranychns pilosus is reported to have 

 become the source of injury to the mulberry in the Trento district of Italy. 



The Rocky Mountain spotted-fever tick, with special reference to the 

 problem of its control in the Bitter Root Valley in Montana, W. D. Hunter 

 and F. C. Bishopp (U. S. Dept. Agr., Bur. Ent. Bui. 105, pp. -'/7, i)ls. 3, figs. 3).— 

 This is a detailed accoimt of studies commenced in 1908 and conducted in 

 cooperation with the Biological Survey of this Department and the Montana 

 Experiment Station. Reports by the Biological Survey (E. S. R., 25, p. 756) 

 and the Montana Station (E. S. R., 20 p. 03) have been previously noted, as 

 has a circular relating to the geographical distribution of this tick (E. S. R., 

 25, p. 59). 



The seasonal histoi-y and habits of Dermacentor vcnustus are dealt with at 

 some length. In lesser altitudes and at the southern limit of the range of the 

 species, activity may begin as early as the middle of February, while in the 

 Bitter Root Valley, it is probable that the ticks seldom become active in 

 numbers before nearly the middle of ^Nlarch. It has been determined that the 

 adults collected on vegetation during the spring months may survive for a 

 period of 413 days without food. Fertilization takes place on the host, and in 

 from 8 to 17 days the females engorge and drop. Deposition may begin as 

 soon as the seventh day after dropping, and all of the eggs, which usually 

 number about 4,000, are deposited within a period of 30 days. In the Bitter 

 Root Valley the period required for incubation ranges from 34 to 51 days, the 

 longer period occurring in the early spring months. At Dallas, Tex., eggs 

 hatched as early as 15 days after deposition, the longest incubation period 

 being 41 days. 



