523 



Eckstein (K.). Zur Bekampfung der Kohlweisslinge. [Measures 

 against Picris s])]).]. — NatNririss. Zeitschr. f. Fors/- h. Landiv., 

 Stuttgart, xviii, no. 8-9, August-September 1920, ])j). 234-235. 



Experiments made with the object of testing the vakie of elderberry 

 (Sambucus nigra) in protecting cabbages against Pieris [R.A.E., A, 

 viii, 141] proved the uselessness of this method. 



Work connected with Insect and Fungus Pests and their Control. — 



Rept. Agiic. Dept. Montserrat, 1918-19, Barbados, 1920, pp. 38-40. 



An ordinance similar to that existing in St. Vincent providing for the 

 destruction of the known food-plants of cotton-stainers {Dysdercus^ 

 was enacted in August 1918 in Montserrat. The destruction of these 

 trees was begun in December 1918, and by April 1919, 1,506 silk -cotton 

 trees were felled. Sida acuHiinafa and S. carpinifolia are also probably 

 alternative food-j)lants, but it still remains to be proved whether they 

 are cajmble of carrying the stainer over from one season to another. 

 The larvae of Prodenia sp. are reported as attacking ajowan [Carum 

 copticum]. A poison-bait containing Paris green and laid down in the 

 vicinity of the seed at sowing time is suggested as a remedial measure. 



EenxVie (J.) & Sutherland (C. H.). On the Life History oi Bacentes 

 {Siphona) geniculata (Diptera : Tachinidae), Parasite of Tipula 

 paludosa (Diptera) and other Species. — Parasitolog//, Cambridge, 

 xii, no. 3, September 1920, pp. 199-211, 1 plate. 



The Tachinid, Bucentes {Siphona) geniculata, is considered to be a 

 normal parasite of Tipula sj)]). • It has been found in T. oleracea, but 

 more frequently in T. paludosa. Other observers have recorded it 

 from the Noctuid Barathra {Mamestra) brassicae, and a related species, 

 SipJwna cristata, from Tipula gigantea. During the winter the larvae 

 remain within their host, but generally leave the latter for pupation ; 

 this occurs in Aju'il in the soil, and lasts about three weeks. A second 

 generation appears about June, the larval period of which lasts about 

 three weeks, and the pupal stage about 17 days. The adult flies of 

 this generation appear towards the end of July. Parasitism of the 

 Tipula larvae probably takes place in the autumn. 



The larva and its structural relations to its host are described. 

 The structure and habits of the adult fly will be dealt with in a 

 subsequent paper. 



Chamberlin (W. J.). The Western Pine Bark-Beetle. A serious 

 Pest of Western Yellow Pine in Oregon. — Oregon Agric. Expt. Sta., 

 Corrallis, Bull. 172, June 1920, 30 pp., 4 plates, 4 figs. [Received 

 9th October 1920.] 



Oregon is one of the most important forest regions of America, 

 containing about one-fifth of the standing timber of the United States. 

 The ])rincipal trees in this vast forest are Douglas fir {Pseudotsiiga 

 taxifolia) and western yellow pine [Pinus ponderosa), and one of the 

 most important insect pests is Dendroctonus brevicomis (western pine 

 bark-beetle). Although the effects of this insect are slow in appearing, 

 it is probably the cause of more dead yellow pine than any other single 

 factor. 



