531 



which seems to be largely instrumental in controlline; the insect. 

 Hormomyia oleiphilu in the larval stage forms galls on the leaves of 

 0. chrysophjlla or on the extremity of the petioles. An ectoparasitic 

 Chalcid has been observed and may be an effective control. Radulella 

 aureocephala, Perrisia chrysopliyllae, P. proxmia and P. verrucosa all 

 form leaf galls on 0. chrysophyUa. 



The larva of Lasioptera carpophila is described from an individual 

 found in the fruit of 0. europaea in the Province of Teramo, and 

 a larva which is probably identical has been observed in olives from 

 Promontorio Garganico. The author takes Dasyneura lathierei and 

 Lasioptera kiefferiana, which in Italy attack 0. europaea, as types 

 of two new genera Gioliella and Gastinella respectively. It is most 

 important that these insects should not be allowed to pass from one 

 continent or district to another. Although it has not yet been 

 proved that U. oleiperda, which is considered peculiar to 0. chrysophyUa 

 and is economically the most important of these species, can also 

 attack the common olive, the mere possibility of its introduction 

 from Eritrea is sufficient to justify precautions until the contrary 

 has been proved. The same applies to Gioliella lathierei and Gastinella 

 kiefferiana. When any of these species occurs in large numbers, the 

 plants attacked should be pruned and the diseased branches topped 

 and immediately burnt. As topping prevents harvesting in the year 

 in which it is carried out, it is best to prune and to spray abundantly 

 with lime water, calcium polysulphide or lime-sulphur mixture, 

 preferably with the addition of a little flour to render the spray more 

 adhesive. 



Scott (E. W.). Abbott (W. S.) & Dudley, Junr. (J E.). Results of 

 Experiments with Miscellaneous Substances against Bedbugs, 

 Cockroaches, Clothes Moths, and Carpet Beetles. — U.S. Dept. 

 Agric, Washington, B.C., Bull. no. 707, 26th August 1918, 36 pp. 



Experiments to test the value of various materials as insecticides 

 against Phyllodromia (Blattella) germanica, L. (common cockroach) 

 were arranged in two series : cage tests and room tests. 



Any ])owdered substance applied to a cockroach, or through which 

 it may crawl, is taken into the mouth, owing to the insect's habit of 

 frequently cleansing its legs and antennae by drawing them through 

 its mouth-parts. In this way any poison, whether distasteful or not, 

 finds its way into the stomach, and therefore there is no necessity 

 for an attractive bait. Of all the substances tested, sodium fluoride 

 was found to be the most effective, acting both as a stomach and 

 contact poison, and killing 100 per cent, in cage tests in 24 hours, 

 even when the material was diluted down to 18 per cent. Practically 

 100 per cent, were killed in kitchens by the use of a mixture con- 

 taining 50 per cent, of sodium fluoride. 



P}Tethrum powder, made from open, half-open or closed flowers, 

 either wild or cultivated, and kept from 1 to 4 years, killed practically 

 all the insects in cage tests within 48 hours. Its effectiveness was 

 greatly reduced by being slightly diluted, even with ground pyrethrum 

 stems, which have no insecticidal value. 



Borax, as an insecticide, acts very slowly, and satisfactory results 

 can be obtained only by the repeated and persistent use of the material. 



