479 



spring and the eggs are laid in rows of 12-30 on the lower side of the 

 leaves, the lower ones being preferred. The larvae appear in May 

 and do more damage than the adults. Pupation takes place in the 

 ground, and the resulting adults give rise to a second generation, 

 the adults of which appear before the autumn and hibernate in cracks 

 in the bark, hollow trunks, or other suitable refuges. The best method 

 of dealing with these beetles is by spraying with lead arsenate or 

 Paris green ; the lower side of the leaves must be well covered to 

 destroy the larvae. Willows with a hairy coating on the lower side 

 of the leaves are not well adapted for spraying, but as feeding by the 

 adults is not confined to the lower side, earlj^ spraying in the spring, 

 when they first appear, is of great value. Tarred boards may be 

 laid beneath the plants for capturing the beetles that are shaken off. 

 Salix viminalis and its varieties are the willows that suffer most from 

 P. vulgatissima, while P. viteUinae prefers the bitter 5. purpurea, 

 though it also often occurs on S. viminalis. 



Het Spirit (Roode Spin). [Mite Injury (Red Spider).] — Plantenziektenk. 

 Dienst, Wageningen, Vlugschr. 36, April 1921, 3 pp. [Received 

 3rd August 1921.] 



This circular on injury due to the mites Tetranychus and Bryohia, 

 and on remedial measures for them, contains substantially the same 

 information as a paper previously noticed [R. A.E., A, vii, 431]. 



Pokziekte van het Pereblad. [Pear Leaf Blister.] — Plantenziektenk. 



Dienst, Wageningen, Vlugschr. 38, May 1921, 2 pp., 1 fig. 

 [Received 3rd August 1921.] 



In early spring the blisters due to Eriophyes pyri, Nal. (pear leaf 

 blister mite) contain the mature female, which deposits 5-6 eggs and 

 then probably dies ; none were found in May. The young mites 

 leave the old blisters and produce new ones on the same or other 

 leaves. They usually hibernate beneath the second and third rows 

 of bud-scales and may be reached by a 1\ per cent, carbolineum 

 spray, applied before the leaf-buds begin to open. For lime-sulphur 

 the date of spraying may be delayed somewhat, provided it is applied 

 before the buds have opened to any extent. 



In summer remedial measures have less chance of success. The 

 infested leaves may be plucked before the mites enter their winter 

 quarters. At the time they are migrating from the old blisters 

 recourse may be had to spraying with sulphur-soap or with a 4 per 

 cent, solution of liver of sulphur, or to dusting with flowers of sulphur. 



Bogdanov-Katkov (N. N.).— flpaKTMHecKafl SHTOMOnorMH, PyKO- 

 BOACTBO K npaKTMHecKMM SaHflTtiflM HO dHTOMonomii (Kypc 

 BblCUJMX yneSHblX SaseAeHlIM). [Practical Entomology. Hand- 

 book of Practical Studies in Entomology (Course for advanced 

 educational Institutions).] — foCyAapCTBeHHOe MSAaieJlbCTBO 

 [Government Publication], Petersburg, pt. 1, 1921, 139 pp., 140 iigs. 



The present volume comprises the first ten lectures delivered at 

 the course of rural economy at the Kamenoostrov institute of agronomy 

 and forestry. It deals with the general structure of insects and their 



