531 



of raiding termites. The Tortricid, Argyroploce aprobola, Meyr., 

 attacks the leaves of Hibiscus ahelmoschus and occasionally cinnamon. 

 As the former is no longer grown in the colony, it is hoped that the 

 infestation will not spread. 



Illingworth (J. F.). The Cane Grub. — Queensland Agric. Jl., 

 Brisbane, xvi, no. 1, July 1921, pp. 50-53, 1 fig. 



Following upon excessive rains in March and April 1921, the effects 

 of submergence on cane grubs [Lepidiota] were studied. After one 

 or two days under water the weaker grubs were dead ; at the end of 

 five days all had succumbed. The effect of flooding was, however, 

 rather disastrous on the canes, causing the terminal shoot to rot, and 

 resulting in a growth of the lateral buds. 



Experiments with arsenic showed that placing it at the bottom of 

 the drill with the plants gave no results, even where 200 lb. were used 

 per acre ; this may, however, have been due to excessive moisture 

 forcing the grubs to the surface, so that they fed on the stalks. Arsenic 

 was much more effective if dusted around the young shoots when 

 about 12 inches high, and used at the rate of about 2001b. per acre. 

 By the time the grubs had reached the second or third stage many of 

 them were destroyed. 



Ceromasia sphenophori having been proved an important parasite 

 of Rhabdocnemis obscura at Babinda, growers are urged to obtain 

 parasitised material from that place, in the form of short lengths of 

 borer-infested cane. These should be placed between the rows in an 

 infested field, and each stalk should be covered with about 1 inch of 

 finely pulverised soil. This should be done in fields that are to stand 

 for two months or more, so that the flies may escape, reproduce, and 

 spread to other fields before the cane is cut. There should be a con- 

 tinuous supply of standing cane in each locality so that the flies can 

 maintain themselves ; if all cane is cut at once the parasites will die 

 out, as the course of a generation only occupies five weeks. A small 

 area left standing every mile or so is sufficient to maintain them, and 

 such areas can be cut later, after the other fields are bearing again. 



Jarvis (E.). The Mealy or Grey-back Cane-beetle. — Queensland 

 Agric. JL, Brisbane, xvi, no. 1, July 1921, pp. 46-50, 1 plate. 



The metamorphosis and external anatomy of the principal sugar- 

 cane beetle of Queensland, Lepidoderma {Lepidiota) albohirtum,Wa.terh., 

 are described and illustrated. The eggs are laid in batches in an 

 irregular-shaped chamber at a sufficient depth in the soil to ensure their 

 remaining damp for at least two weeks, the number reaching an average 

 of about 27 eggs per female. The third instar larva is described in 

 order to avoid confusion with that of Lepidiota frenchi, Blackb., 

 L. consobrinus, Gir., and L. caudata, Blackb., all of which, however, 

 are slightly darker and decidedly opaque, besides having different 

 arrangements of the anal patch and surrounding bristles. Pupae are 

 found in the soil at depths varying from 4 to 15 inches, the variations 

 probably being due to several factors, such as temperature, moisture, 

 drainage and the mechanical condition of infested lands. Pupation 

 generally occurs directly under the stools that have been attacked, 

 probably owing to the added moisture of the soil. The pupal chamber 

 is constructed in such a manner as to exclude small insect enemies 



