ini6] ECONOMIC ZOOLOGY ENTOMOLOGY. 357 



Thrips oryzae n. sp., injurious to rice in India, C. B. Williams (Bui. Ent. 

 Rcnearch, 6 {1916), No. 4, PP- 353-355, fig. 1).— This species is reported to be 

 injurious to young rice. 



What cacao thrips signify in Grenada, H. A. Ballou (Agr. News [Bar- 

 bados], llf (1915), No. 350, pp. 3U, 315).— The cacao thrips (Heliothrips 

 rubrocinctus) probably occurs in all parts of Grenada, where it was first 

 found in 1898, and may occur in every cacao field. Attacks occur year after 

 year on the same areas, on the same trees even, sometimes spreading a little, 

 but a thrips area one year is liable or certain to be a thrips area every year, al- 

 though it may never increase in numbers sufficiently to attract attention or 

 cau.se any injury. 



It is suggested that the cacao thrips should be considered a useful insect 

 since it may indicate that the trees are suffering from untoward condition, 

 thus serving as an indicator. When thrips areas have been examined, it has 

 been found that root disease was present, the drainage was insufficient, the 

 soil was shallow with terrace or heavy clay beneath, or there was evidently a 

 lack of humus in the soil. 



A new thrips damaging coffee in British East Africa, C. B. Williams 

 (Bid. Ent. Research, 6 (1915), No. 3, pp. 269-272, fig. l).—Diarthrothrips 

 coffece n. g. and n. sp. is said to have caused serious damage to the leaves of 

 coffee in several districts of British East Africa. 



Egg and manner of oviposition of Lyctus planicollis, T. E. Snyder (U. B, 

 Dcpt. Agr., Jour. Agr. Research, 6 (1916), No. 7, pp. 273-276, pis. 4).— Species 

 of the genus Lyctus are said to be by far the most important of the various 

 beetles which cause the so-called " powder-post " injury to seasoned wood 

 products so widely distributed over the world. The observations of L. plani- 

 cnlUs here described were made at Washington, D. C, and Falls Church, Va. 



The winter is passed in the larval stage, general pupation occurring about 

 the first of April ; the pupal cell is excavated near the surface of the wood, 

 and to this cell the larvre retreat after cutting a transverse burrow nearly to 

 the surface for the exit of the adults. The general emergence of adults takes 

 place during May. Oviposition began a few days after mating and was 

 observed to take place principally during the middle of May in 1915. On 

 May 24 many beetles were observed on radial sections of wood with their ovi- 

 positors deeply inserted into the open pores or large longitudinal vessels in 

 the wood. The beetles seem to prefer to oviposit on those sections of seasoned 

 sapwood where the open ends of pores are most numerous. Recently hatched 

 larvse were first observed on June 1, the period of incubation being 10 days 

 at most. 



It is stated that the injury by " powder-post " beetles to unfinished seasoned 

 wood products can be prevented by simply adapting a system of inspection, 

 classification, and methods of disposal of stock to facts in the seasonal history 

 of the insects, as has been recommended by Hopkins (E. S. R., 24, p. 256). In 

 the case of finished wood products it may often be practicable to treat the wood 

 with substances to prevent attack. Judging from the facts in the seasonal 

 history of this species, preventives should be applied before March 1. 



The mealy bug of the muscat grape, F. K. Howard (Mo. Bui. Com. Hort. 

 Cat., 5 (1916), No. 2, pp. 67, 68, fig. 1).—The infestation of table and wine grapes 

 in the grape-growing section of the San Joaquin Valley by the mealy bug, 

 probably Pseudococcus bakeri, first became of economic importance in 1914. 

 It was first found on raisin grapes in an old muscat vineyard near Armona, 

 Kings County, Cal., in September, 1915. Up to the time of writing no satis- 

 factory control measure had been worked out. 



