344 



in soil in the laboratory, without injury to the roots of a sugar-cane. 

 The high price of this substance renders its use on a large scale imprac- 

 ticable. (2) Potassium cyanide (1 lb. to 200 gals, water) was fatal to 

 100 per cent, of larvae under the same conditions as in the previous 

 experiment. A plant 2 feet high treated with 8 qts. of the solution 

 showed a slight wilting of the leaves after 24 hours, but recovered a 

 week later. The Mamelle method of injecting potassium cyanide 

 received preliminary tests and gave satisfactory results. (3) Borax 

 (1 lb. to 3 gals, water) proved efficient, but was too expensive for 

 extensive use. (4) Creosote emulsion (8 oz. creosote to 5 gals, water) 

 proved suitable. Solutions of saltpetre (1 lb. to 3 gals.), barium 

 chloride (1 lb. to 3 gals.) and hellebore (1 lb. to 12 gals.) gave negative 

 results. The last-named substance had been in stock for about a year 

 and may in consequence have lost its insecticidal properties. 



Jarvis (E.). Notes on Insects Damaging Sugar-Cane in Queensland. — 



Queensland Bureau of Sugar Expt. Sta., Div., Entom., Brisbane, 

 Bull. no. 3, 1916, 48 pp., 4 plates. [Received 14th June 1916.] 



Insect pests of sugar-cane in Queensland include those attacking 

 (1) the stalk and mid-rib of the leaf ; (2) the stalk and " sets " below 

 ground ; (3) the foliage ; (4) the roots ; and (5) those feeding on the 

 sap. In the first group, the Noctuid, Phragmati'phila truncata, Walk., 

 occurs also in South Austraha and Tasmania, and is chiefly injurious 

 to young shoots in September and October. Pupation takes place 

 in the tunnels or among the bases of dead canes or leaf-sheaths. The 

 duration of this stage in November is 12 days at a temperature of 

 77° F. Small holes bored through affected stems by the larvae allow 

 of the entrance of predaceous enemies, especially the ant, Pheidole 

 megacephala. The latter would probably prove an effective controlUng 

 agent, but should not be encouraged in fields in which Rhabdocnemis 

 obscurus is present, since it destroys the Dipterous parasites of this 

 insect. Larvae of P. truncata are parasitised by an undetermined 

 Tachinid fly and in New South Wales by the Hymenopteron, Apanteles 

 nonagriae ; the pupa is parasitised by Ewplectus howardi. Diatraea 

 saccharalis, F., is controlled to a great extent by egg-parasites and 

 cannot be regarded as a serious pest. Rhabdocnemis obscurus, Boisd., 

 causes considerable annual loss in the Johnstone River district. The 

 Tachinid parasite, Ceromasia sphenopJiori, VilL, has been liberated in 

 affected localities. Artificial methods of control include clean culti- 

 vation and the use of short pieces of split cane as traps. A P3Talid, 

 Polychroa sp., was recorded for the first time in November 1915 

 at Pyramid, where young ratoon shoots were injured. Pupation was 

 observed to take place in the tunnel in the middle of the shoot. In 

 the laboratory this stage lasted from 22nd November until 12th 

 December. The Tineid, 0])ogona glycyphaga, Meyr., may prove 

 injurious to soft varieties of cane by boring into the stem and feeding 

 on the leaf-sheaths. The leaf-stalks of banana and the fruits of 

 granadilla may also be attacked by the larvae. Pupation takes place 

 in a cocoon formed between the sheath and the stem [see this Review, 

 Ser. A, iii, p. 364]. A Chalcid parasite, Stotnatoceras gracilicorpus, Gir., 

 has been reared from the pupa. The Elachistid, Cosmopieryx sp., bores 



