356 



t)EwiTZ (J.). Ueber die Einwirkung der Pflanzenschmarotzw auf die 

 Wirtpflanze. [The Action of Plant Parasites on their Host- 

 plant.] — Natiirwiss. Zeitschr. f. Forst- u. Landvurtsch., Stuttgart, 

 xiii, no. 6-7, June-July 1915, pp. 288-294. [Received 10th June 

 1920.] 

 Most work relating to parasites of plants deals with the outward 

 changes caused to the host. Very little has been done concerning the 

 effect on the internal organism. 



As a result of experiments with an Aphid infesting Pelargonium it 

 has been ascertained that an extract obtained from the bodies of this 

 insect exercises a haemolytic action on the red corpuscles in the blood 

 of cattle, so that it is evident that this Aphid contains a toxin. 



ScHWANGART (F.). UebcF Rebcnschadlinge und -nutzlinge. iv. 



Vorstudien zur biologischen Bekarapfung des " Springwurms " der 



Rebe {Oenophthini pillenana, Schiff.)- [Insects injurious and 



beneficial to the Grape Vine. iv. Preliminary Studies on the 



Biological Control of 0. pilleriana.] — Naturwiss. Zeitschr. f. Forst- 



II. Landwirtsch., Stuttgart, xiii, nos. 8-9 & 11-12, August-September 



& November-December 1915. pp. 380-408 & 522-541. [Received 



10th June 1920.] 



An account is given of a careful study of Sparganothis (Oenophthira) 



piUeriana, Schiff., a pest of the grape-vine, the work having been begun 



in 191 1. A list of the parasites of this moth is given, and two methods 



of planting are advised against it and allied Lepidopterous pests. 



One aims at utilising against each other the following : — Hyponomeuta 



nuilitieUus, found on apple ; H. padellus on Primus ; and the vine 



moths, S. piUeriana, Clysia ambiguella and Polychrosis hotrana. The 



other makes use of Hyponomeuta padellus, found on Euonymus. All 



these insects, according to the date on which they appear and the 



parasites they harbour, form links in a " host-cycle." To promote 



this and thus favour the natural enemies and adversely afiect the 



plant pests, resort to such planting methods as follow is advised. If 



it is intended to use the five pests mentioned, Prunus and apple must 



be planted in vine-growing districts and grape-vines must be planted 



beneath the fruit trees in an orchard district. It is always advisable 



to mingle stone-fruit with apples and pears, as the different species of 



Hyponomeuta occurring on these plants are not always likely to appear 



in equal numbers in a given year. This method of interplanting has 



a number of limitations, and recourse must also be had to a wild plant, 



Euonymus, which harbours Hyponomeuta cognatellus. Euonymus 



needs no attention, does not impoverish the soil, does not throw a shade 



injurious to the vine, and may be planted in situations unsuitable for 



fruit trees. Furthermore H. cognatellus may be allowed to develop 



in numbers that cannot be permitted to H. malinellus or H. padellus, 



which are injurious to fruit-trees, 



ScHEiDTEB (F.). Ueber die Eiablage von Saperda populnea, L. 



[The Oviposition of S. populnea.] — Naturwiss. Zeitschr. f. Forst- 



u. Landwirtsch., Stuttgart, xv, no. 4-6, April-June 1917, pp. 113- 



128. [Received 10th June 1920.] 



The oviposition of Saperda populnea, L., on poplar in Bavaria is 



described in detail. The female makes a curved furrow in the bark 



