362 EXPERIMEN'T STATION RECORD. 



Some parasites of Lasius fuliginosus, L. niger, and L, flavus, W. C. Craw- 

 ley (Ent. Rec. and Jour. Vai-^iation, 23 (1911), No. 1, pp. 22, 23). — The occur- 

 rence of Anteimophorus grandis, as a parasite of aut larvje, is reported. In 

 one nest as liigh as 12 per cent of the ants were found to be infested by this 

 mite. 



A new sawfly of economic importance, S. A. Rohwer {Ent. News, 22 

 (1911), No. 6, pp. 263-265, figs. 6). — Ciiliroa (Eriocatnpo'ulcs) amygdaUna which 

 has been found to defoliate peaches in the vicinity of Tallulah, La., is described 

 as new to science. 



Technical papers on miscellaneous forest insects. — IV, Studies in the 

 sawfly genus Hoplocampa, S. A. Hohweb (U. 8. Dept. Agr., Bur. Ent. Bui. 

 20, pt. Ji, tech. scr., pp. 139-lJi8, pis. //, fig. 1). — This second paper on sawflies 

 (E. S. R., 24, p. CG2) includes descriptions of 10 new species of Hoplocampa. 

 A synoptic table of the Nearctic siiecies of the subgenus Hoplocampa is in- 

 cluded. 



An insect injurious to spruce trees, A. H. Cockayne (Jour. New Zeal. Dept. 

 Agr., 2 (1911), No. 3, pp. 117-121, figs. 2). — A species of red spider closely re- 

 lated to Tetranychus lyimaculatus is reported to have become the source of con- 

 siderable injury to various species of Abies, especially A. menziesii, in the 

 South Canterbury district of New Zealand. Infestation is first manifested by a 

 yellowing of the leaves of young branches. The leaves soon become dry and 

 fall off. 



The Colorado laws governing horticultural inspection (Ann. Rpt. Bd. 

 Hort. Colo., 1910, pp. 217-228). — The regulations and insecticide and fungicide 

 formulas adopted by the State Board of Horticulture are presented with the 

 laws governing horticultural inspection. 



A contribution to our knowledge of insecticides, C- T. McClintock, E. M. 

 Houghton, and H. C. Hamilton (Rpt. Mich. Acad. Sd., 10 (1908), pp. 197-208, 

 pi. 1; reprint). — "The work reported in this paper has to do with the contact 

 insecticides only. . . . 



" The insecticidal, germicidal, and toxic values (for higher animals) have 

 little or no correlation. It is possible to determine the relative strength or 

 value of insecticides by immersing test insects in definite strengths of the in- 

 secticide, and noting the time required to produce death. The common bedbug 

 (Cimex lectularis) appears to be the most satisfactory test insect. As yet the 

 mode of action, the way in which the contact insecticides cause the death of 

 the insects, has not been determined. Apparently the fewer the number of 

 spiracles, the smaller their size, and the better they are guarded by hairs or 

 valves, the more resistant is the Insect to the contact insecticides. 



" Chemical standardization of this class of insecticides is with our present 

 knowledge impossible. With 2 substances, having essentially the same chemical 

 composition, the insecticidal values may vary enormously. Even the same 

 substance, prepared with what are apparently unimportant chemical variations, 

 gives widely different insecticidal values." 



A further contribution to our knowledge of insecticides, C. T. McClin- 

 tock, H. C. Hamilton, and F, B, Lowe (Jour. A)ncr. Pub. Health Assoc., 1 

 (1911), No. 4, pp. 227-238, pi. 1). — "It is possible to standardize substances 

 which are subject to sophistication or deterioration by comparing the efficient 

 dilution of their vapors with that of a product of known purity. This is par- 

 ticularly applicable to solutions of nicotin and to powdered chrysanthemum 

 flowers. As yet there is nothing from which to conclude what action the vapors 

 have on the insects. If it were merely irritative, formaldehyde would be 

 valuable and the vapors of burning insect powder without value. If the action 



