158 



Reh (L.). Zur Ausgestaltimg der angewandten Entomologie in 



Deutschland. [The Development of Applied Entomology in 



Germany.] — Zeitschr.f. angew. Entomologie, Berlin, ii, no. 1, 1915, 



pp. 225-228. (Abstract in Zeitschr. f. Pflanzenkrankh., Stuttgart, 



xxviii, no. 3-4, 1st June 1918, p. 158.) 



The view is expressed that the development of applied entomology 



in Germany should proceed along the lines of scientific research, 



practical work and teaching. For research, institutes are required 



with modern equipment and placed under the control of a zoologist 



or entomologist and not, as hitherto the case in Germany, under a 



botanist. Practical work requires field-stations, such as are found 



in the United States. Teaching must be closely related to practice, 



and field-stations must therefore be added to existing instruction 



centres. Liberal financial assistance must be given where applied 



entomology is concerned, in view of the enormous losses due to the 



ravages of insects. 



Reh (L.). Dungung und Insektenbefall. [Manuring and Insect 

 Infestation.] — Zeitschr. f. angew. Entomologie, Berlin, iii, 1916, 

 pp. 127-133. 



Hoffmann ( — ). Dungung und Insektenbefall. [Manuring and Insect 

 Infestation.] — Ibidem, 257-262. (Abstract in Zeitschr. f. Pflanzen- 

 krankh., Stuttgart, xxviii, no. 3-4, 1st June 1918. pp. 158-160.) 



^oth these papers discuss the effects of manure on insect pests. 

 A case is recorded of a severe outbreak of Hyponomeuta malinellus 

 and H. variabilis in which trees standing in grassland were less infested 

 than those in cultivated ground, and under similar conditions of 

 cultivation manured trees suffered the most. The opinion is expressed 

 by the first author that cultivated plants are preferred by insects to 

 wild ones and that sometimes this preference is shown for cultivated 

 plants very different from the original wild food- plant . Cultivation on a 

 large scale has been held to be the reason for the increase in infestation, 

 but this does not explain why the plants that are most carefully 

 grown, such as the finest varieties of the apple, should suffer most. 

 Young, growing plants are also preferred, and the use of trap-crops 

 depends on this fact. 



Regarding the influence of various manures on plants, stable 

 manure or any manure containing nitrogen, such as saltpetre, increases 

 the water-content of plants and makes them richer in albumen and 

 starch. Fruit-trees thus manured are particularly liable to canker 

 and to infestation by Aphids, Coccids and red spider [Tetranychus]. 

 Lime and phosphorus on the contrary reduce the number of insect 

 pests. It is therefore necessary to ascertain in the case of each pest 

 which manures are favourable or otherwise to its increase. 



ScHEiDTER (F.). Tierische Schadlinge an Geholzen. [Insect Pests of 

 Forest Trees.] — Mitt. Deutsche Dendrol. Gesellsch., 1916, pp. 210- 

 225, 13 plates. (Abstract in Zeitschr. f. Pflanzenkrankh., 

 Stuttgart, xxviii, no. 3-4, 1st June 1918, pp. 160-162.) 



Much damage is recorded to the leaves of sugar-maple by the 

 adults of Phyllobius psittacinus. Germ., and the larvae of this beetle 

 were even more harmful in spruce plantations by destroying the bark 

 of the entire root-system. The adult beetles seldom attack conifers. 



