524 



Starvation and the heat of the sun soon kill the locusts. As these 

 insects are attracted by light, it is easy to lead them to a pit where 

 they will pile themselves up to a height of 30 feet or more. Putrefaction 

 is prevented by adding dry phosphates and plaster to the mass from 

 time to time. A rich compost is produced and this may easily be 

 removed by means of a tunnel connecting the bottom of the pit with 

 the hill-side. If it is not desired to capture the locusts, nets of 1 inch 

 mesh should be impregnated with heavy oil or with a suitable virus 

 in dilute solution. The insects will be contaminated in flying through 

 the netting and their destruction will soon result. The author states 

 that during 23 years he has in vain drawn the attention of the 

 authorities to the advantages offered by nets in locust destruction. 



Berlese (A.). La distruzione della Diaspis pentagona a mezzo 

 della Prospaltella herlesei. [The destruction of Aulacaspis pentagona 

 by Prospaltella herlesei.'] — Redia, Firenze, x, pts. 1-2, 20tli May 

 191.5, pp. 1.51-218. 



It is stated that by the end of 1914 the destruction of Aulacaspis 

 pentagona by Prospaltella herlesei was nearly completed and the special 

 legislation regarding it had been abrogated. Parasitised material has 

 been dispatched to the Argentine and Switzerland with excellent 

 results, while this method of control has been begun in Spain. 

 A bibliography of 177 references is included in this paper. 



Del Guercio (G.). Ulterior! ricerche sullo stremenzimento o incap- 

 pucciamento del Trifoglio. [Further research on the stunting or 

 curling of clover.] — Redia, Firenze, x, pts. 1-2, 20th May 1915. 

 pp. 235-301, 42 figs. 



This condition of common clover, which is not necessarily due to 

 insect attack, was first noticed by the author in Tuscany in 1911. 

 The affected plants were attacked by various insect pests. A Scolytid 

 beetle, Hylastes trifoUi, was found in the roots ; where such infestation 

 was rare or in its initial stage, considerable infestation of the stems by 

 a weevil, Apion virens, and of the heads of clover by A. apricans was 

 noticed. Other insects included Thysanoptera, Cecidomyids and Aphids. 

 Of these, the Cecidomyid larvae are of serious economic importance. Of 

 the Nematodes, Tylenchus devastatrix deserves special mention. Hetero- 

 rferaspp. are of less importance. Tylenchus s-p-p. are found in the clover 

 roots from the spring of one year to that of the next. Subject to 

 natural interruptions, this is also the case with Cecidomyid larvae. 

 Hi/lastes and Apion spp. occur from early spring up to late autumn. 

 The imagines of the latter then issue from the stems and hibernate 

 at the base of the flowers in the head, while Hylastes remains in the 

 root during winter. Should the plants have suffered to such a degree 

 as no longer to afford sufficient nutriment, the Hylastes migrate from 

 them to stronger plants. In spite of the assertions of systematic 

 workers, the Scolytid of clover is pecuhar to this plant and does not 

 migrate. 



