373 



accounting for 67-8 per cent., or 52-4 per cent, of the 282 olives. 

 Such a high percentage of parasitism is of less importance than is 

 at first apparent, for it is due to the fact that by 26th December the 

 number of olives — and in consequence the number of larvae exposed 

 to parasitism — was small. The difficulty of ascertaining the number 

 of fruits left on the trees in winter and the percentage of parasitism 

 hinders an estimate of the infestation likely to occur in the following 

 season. These factors may explain why a year of severe losses may be 

 followed by a similar one. 



Malexotti (E.). II Problema attuale della Mosca delle Olive in 

 Maremma. [The present Problem of the Olive Fly in the Maremma 

 District of Tuscany.] — Minist. Agric, Direzione Gen. Agric, 

 Rome, 1921, 20 pp. [Received 16th May 1922.] 



In this address to agriculturists in the province of Pisa, it is pointed 

 out that the molasses used to sweeten the poison spray against the olive 

 fly [Daciis oleae] does not promote the development of the sooty fungus, 

 Capnodimn oleae. In advocating the formation of defence syndicates 

 it is advised that these should be free, voluntary organisations unless 

 at least one half of the olive trees in a given district belong to members, 

 when defence measures can assume a compulsory character without 

 leading to the compUcations bound to ensue if a minority seeks to use 

 compulsion. 



Malenotti (E.). La Lotta contro le Cavallette nel Bacino del Fueino 



nel 1920. [Anti- Locust Work in the Basin of the Fueino in 1920.] 

 — Nuovi Ann. Minist. Agric, Rome, i, no. 1, June 1921, 

 pp. 63-84, 1 map. [Received 16th May 1922.] 



The infestation by Calliptamus italicus in the district of Fueino, 

 which is the drained bed of a lake encircled b}^ some of the mountains 

 in the Abruzzi region, is of recent date, having first appeared in 1918. 

 It is due to a local increase of this locust, favoured by the extension 

 of bare, sunny stretches resulting from deforestation and of hard, 

 unworked soil consequent on decreased cultivation after the earthquake 

 of 1915. Furthermore, in 1919 and 1920 the weather was very dry 

 in spring, which is the season in which this locust develops. 



The swarms of C. italicus, consisted mainly of the form margincllns, 

 Serv. Some specimens of Ocdipoda coerulescens and Tettigonia 

 {Dectictis) albifrons were observed. In 1920 the first newly-hatched 

 individuals were found in mid-May, the majority appearing at the 

 end of May. In some places a second and distinct hatching was 

 observed on 26th June, indicating a second oviposition. The first 

 winged forms occurred on 21st June, and mating began on 12th July. 

 Oviposition took place in August. 



It is not feasible to draw up a simple list of preferred food-plants, 

 as they vary according to the stage of development of the locust and 

 the num.ber of various plants available. For instance, nymphs having 

 available cabbages, onions, tomatos, artichokes and peppers, preferred 

 the last-named, though they had been sprayed with lime-sulphur, to 

 the exclusion of the others. In another case, where peppers were 

 lacking, artichokes were destroyed. It may, however, be said that 

 in the Fueino district the preferred plants are such Leguminosae as 

 lentils, vetches and clover, and then potatoes, maize and garden vege- 

 tables. A large number of wild grasses were also eaten. Bushes and 



