518 



degree that in some localities spraying is not carried out. All oranges, 

 and such lemons as are intended for table consumption, must be clean, 

 whereas lemons for industrial purposes need not be so scrupulously 

 free from infestation ; this difference requires to be borne ni mind 

 when calculating the cost of remedial measures. 



Stellwaag (F). Neuzeitliche Schadlingsbekampfung im Obst- und 



Gemusebau. [Modem Pest Control in Fruit and Vegetable Culti- 

 vation.]— H^z>s6at?m, R. Bechtold & Co., 1922, viii + 116 pp., 40 

 figs. Price 150 marks. 



This small volume gives the fruit and vegetable grower accurate, 

 practical and concise information on insect pests and their habits, and 

 on the preventive and remedial measures best adapted to combat them. 

 The text is arranged according to the plants affected, each heading being 

 divided according to the injury caused. The final chapters on artificial 

 and biological measures are followed by a full index. 



MtJLLER (A.) & Rasch (W.) . Schadliche Insekten und Nager. [Injurious 

 Insects and Rodents.] — Frankfurt a. Main, Deutsche Gesell- 

 schaft fiir Schadlingsbekampfung, 1922, 23 pp., 2 col. pis. 



The pests dealt with include the principal insects attacking man or his 

 household goods and foodstuffs. In the case of each insect general 

 notes are followed by short descriptions of the various stages and of 

 their biology. The aim of this pamphlet is to popularise exact informa- 

 tion regarding these pests, and this is achieved in a simple and effective 

 manner. 



Pemberton (C. E.). Mites and other Organisms in their possible 

 Relation to Sugar Cane Root-rot in Hawaii. — Hawaiian Planters' 

 Record, Honolulu, xxvi, no. 3, July 1922, pp. 145-147, 1 fig. 



Extensive injury to sugar-cane roots, which does not appear to 

 be due to fungi, has been observed in Hawaii in both young and 

 mature plants and in ratoons. Holes were abundant in tender, growing 

 roots from the tip to the base, scattered through dead roots and particu- 

 larly common in small roots just starting. A minute brownish mite has 

 been found wherever the typical root injury occurs, but its real import- 

 ance has yet to be determined. Other possible cane root feeders are 

 other Acarids, Nematodes, ants and active Crustaceans. It is too early 

 to state definitely the part played by mites and other animal organisms 

 in the formation of these root-holes, but the recognition of the injury 

 opens a new field for biological investigation. 



Williams (F. X.). Entomological Work in the Philippines, September 



1920-April 1922. — Hawaiian Planters' Record, Honolulu, xxvi, 

 no. 3, July 1922, pp. 173-177. 



The work done from September 1920 to April 1922 included attempts 

 to secure natural enemies, for importation into Hawaii, of the wire- 

 worms, Monocrepidius exul and Simodactylus cinnamomeus, which 

 damage sugar-cane fields there, and to import the fig wasp which 

 pollinates the flowers of Ficus retusa. 



Wireworms are not a recognised pest in the Philippines, and 

 no' parasites were found. Several shipments of figs of Ficus retusa 

 bearing fig insects [Blastophaga) were made to Hawaii, but neither those 

 from the Philippines nor those from Hongkong yielded the proper species. 



