21 



question of the effect of volcano fumes upon Paranagrus optabilis has 

 frequently been discussed, experiments in this connection were under- 

 taken, and indicate that it is entirely unaffected by these fumes. 



The practice of stripping off the low green leaves of infested cane 

 and allowing them to remain on the ground, with a view to reducing 

 the number of hoppers without destroying the parasites, is undoubtedly 

 beneficial in localities where the rainfall and humidity are low, but is 

 useless in the upper fields in localities where rain is frequent and 

 humidity high, as the leaves remain in a soft condition and allow both 

 hoppers and parasites to hatch. The distance and rapidity of dissem- 

 ination of P. optabilis have not yet been accurately determined, but 

 are being ascertained by experiment. 



In the examination of 5,361 individuals of the leaf -hopper, only 

 27 '7% were males; no infertile eggs have, however, been found in cane, 

 though the species is not parthenogenetic. Only 43 of these 5,361 

 individuals were parasitised by flies of the genus Pipunculus ; no 

 Dryinid parasites were found among them and Ootetmstichusformosanus 

 was rare. 



Remedial measures against the leaf -hopper include the use of contact 

 sprays ; while these have never been tried to any extent, it is felt that 

 there are possibilities in the application of a good spray where hoppers 

 are abundant and within reach of such treatment. Descriptions and 

 illustrations are given of suitable parasite hatcheries and field shed 

 boxes for use in the distribution of parasites, which are considered to be 

 the chief factor in the reduction of leaf-hoppers. They are particularly 

 successful in fields where the hoppers have not had time to become 

 numerous, where there are few eggs and, in consequence, few parasites. 

 By liberating parasites in such fields the percentage of parasitism is 

 quickly raised and the leaf-hopper infestation reduced to a minimum. 

 It is pointed out that the distribution of parasites as a measure for 

 hopper control is of little use unless carried out on a large scale. 

 When boxes containing leaf midribs infested with parasitised eggs are 

 used in fields of young cane, one box for every two acres is considered 

 sufficient. Each box should contain from 2,000 to 4,000 midribs and 

 these should be frequently replaced, the work being continued for 

 at least three months. 



Haswell (W. a.). Wheat, Weevils and Bulk-Handling.— /Sciewce 

 and Industry, Melbourne, i, no. 5, September 1919, pp. 304-307. 



Attention is drawn to the increased dahger of weevil infestation in 

 wheat handled in bulk in Australia. Even when stored wheat is 

 apparently shielded from rain and damp soil, it is able during certain 

 stages in maturing to absorb moisture from the air, thus becoming a 

 more favourable medium for the increase of grain weevils such as 

 Calandra granaria and C. oryzae. The remedial measure advocated is 

 airtight storage [R. A. E.,A, vii, 94, 529]. 



Hinds (W. E.). Report of Entomologist.— 5i5^ Ann. Rept. Alabama 

 Agric. Expt. Sia., Auburn, January 1919, pp. 27-29. [Received 

 20th November 1919.] 



The use of trap-crops for concentrating the first generation of 

 Calandra and other species, so that they may be destroyed while still 



