1917] ENTOMOLOGY. 257 



eating beetles C. ruflcornis and D. graminca. Further experiments with the 

 ' changa ' showed that almost perfect control may be obtained by surrounding 

 the young plants when they are planted out in the field with a ring of the Paris 

 green and flour mixture. This mixture consists of 3 per cent Paris green and 

 97 per cent of a flour high in gluten." 



Important foreign insect pests collected on imported nursery stock in 

 1916, E. K. Sasscer (Jour. Econ. Ent., 10 (1917), No. 1, pp. 219-223).— K sum- 

 mary of the more important results of Federal inspection work. 



Some methods of colonizing imported parasites and determining their 

 increase and spread, S. S. Crossman {Jour. Econ. Ent., 10 (1917), No. 1, pp. 

 177-183, fig. 1). — The author describes the methods made use of at the Gipsy 

 Moth Laboratory of the Bureau of Entomologj- of the U. S. Department of 

 Agriculture. 



Efficiency and economy in grasshopper control, E. D. Ball (Jour. Econ. 

 Ent., 10 (1917), No. 1, pp. 135-139, fig. 1). — The author describes a grasshopper 

 catching machine which is efficient, inexpensive, and when once built is always 

 ready for immediate use. The details of its construction have been given in a 

 bulletin previously noted (E. S. R., 33, p. 59). The machine takes 24 ft. at a 

 sweep, and 40 acres can be covered in a day. 



The seventeen-year locust in western New York, C. H. Hadley, jr. and R. 

 Matheson (Jour. Econ. Ent., 10 (1917), No. 1, pp. 38-41). — The authors record 

 the occurrence of this insect during the summer of 1916. 



Biological and systematic notes on British Thysanoptera, C. B. Williams 

 (Entomologist, 1,9 (1916), No,s. 641, pp. 221-227, fig. 1; 642, pp. 243-245; 643, 

 pp. 275-284)- — The author's studies have led to the conclusion that the Ameri- 

 can pear thrips (Tccniotlirips pyri) is no other than T. inconsequens, a species 

 which has been known to occur in England for nearly 100 years, and which does 

 not usually cause much injury in Europe. The author considers it practically 

 certain that the species was introduced into California from Europe in the 

 larval or pupal stage in the soil attached to the roots of fruit trees. Its spread 

 from there to other parts of the United States, and recently into Canada, may 

 have been by the same means, or by the rapid transference of adults by railway 

 trains, etc., or it is possible that a fresh introduction from Europe might have 

 occurred. Its distribution as now known includes Bohemia, Italy, England, the 

 United States, and Canada. 



In further notes on the pea thrips Eakothrips pisivora (E. S. R., 34, p. 450), 

 it Is stated that during 1915 the damage which it caused was more severe than 

 ever before noticed. " By June 25 first and second stage larvae were abundant 

 in all the flowers and on the pods, and by July 5, when nearly all the larvae 

 were large, over 60 per cent of all the pods were more or less severely damaged 

 by them. In nearly all cases the pods nearest the base of the plants, that is the 

 earlier ones, were almost undamaged, while those near the top were so se- 

 verely attacked that in many cases the flower dried up without setting any pod, 

 while those pods which did start were small, deformed, and contained no seed 

 at all. 



" Most of the larvae were feeding quite openly on the pods, only a few being 

 hidden by the remains of the flower, and specimens examined during the night 

 were found to be as active then as during the daytime. At this stage it would 

 be possible to kill a large percentage by spraying. On July 7 there was an ex- 

 tremely heavy, almost tropical rainstorm, yet immediately after it quite a 

 large number of larvae were still feeding openly on the pods, chiefly on the 

 lower surfaces. In the first fortnight in July nearly all the larvae descended, 

 but a few fed ones were found on till the end of July." 



Notes on its natural enemies and host plants are included. 



