415 



Other British Aphids that are casual pests are Macrosiphiim lactucae, 

 L., M. spnchi, L., and A. gossypii, Glover. The only other Aphids 

 recorded from species of Solanum in various parts of the world are 

 A. solanella, Theo., A. nerii, Kalt, A. silybi, Pass., Macwsiphnm tahaci, 

 Perg., Megonra solani, Thomas, and Trifidaphis radicicola, Essig. 



Cendana (S. M.). The Banana Weevil— Philippine Agric, Los 

 Banos, x, no. 8, March 1922, pp. 367-376, 3 plates. 



Various records of Cosmopolites sordidus, Germ, (banana weevil) 

 since its first description in 1824 up to 1920 are reviewed. In the 

 Philippines the beetle is also a serious pest of abaca {Musa textilis). 

 Its habits and the injury caused by it are described. Natural enemies 

 appear to be absent, although a Chalcid has been found in one of the 

 breeding cages when the insects were confined in the insectary. The 

 medium and small varieties of banana are apparently more subject 

 to attack than the larger ones. It is possible that bananas may 

 prove useful as a trap crop for the protection of abaca, but this point 

 requires further investigation. Under laboratory conditions the hfe- 

 cycle from egg to adult varies from 52-56 days, the length of the 

 larval stage being from 42-45 days. There are probably not more 

 than five generations a year. 



Infestation is spread chiefly by the transportation of infested suckers 

 and root stocks ; to avoid this they should be soaked in water for at 

 least 72 hours. Clean cultivation and crop rotation should be 

 practised ; very old plantations should be cut down and the land 

 ploughed up. 



Johnston (T. H.). Report on Investigations regarding Prickly-Pear 



Control by Biological Means.— Queensland Agric. Jl., Brisbane 

 xvii, no. 5, May 1922, pp. 238-240. 

 The governments of the Commonwealth, Queensland and New South 

 Wales have co-operated in a scheme of investigations with a view to 

 controlhng prickly-pear by means of natural enemies. Of eight species 

 of fungi experimented with, only one, Gloeosporiimi lunatum, promises 

 to be of any real value, but it has not yet been tried in the field. A 

 bacterial disease was discovered in Florida in 1920, and the organism 

 causing it has proved to be capable of giving rise to a very virulent 

 disease among all kinds of prickly-pear naturahsed in Queensland 

 and New South Wales. Its dissemination, however, depaids upon 

 inoculation of each joint, and it is hoped that certain insect enemies 

 of cacti will be of use in carrying the disease in this manner. There 

 are three species of moths that show promise of usefulness in this 

 respect ; two of these are borers {Melitara spp.), of which one, from 

 Florida, has as yet failed to become established, while the other, from 

 Texas, is doing excellent work, and is capable of attacking and 

 destroying all the various kinds of prickly-pears now naturalised in 

 Australia, though apparently preferring the two commonest. The 

 newly hatched larvae begin the destruction and continue for about 

 three months, when they pupate, the adults emerging about one month 

 later. A bacterial disease kills many of the caterpillars. The other 

 useful moth is Mimorista sp., which in its larval stage rapidly destroys 

 the young joints of prickly-pear. The wounds caused by these enemies 

 are frequently invaded by scavenger flies; but though numbers of 

 Stratiomyiids, Syrphids, and others have been bred out in Brisbane from 

 material received from abroad, none has become established. Further 

 attempts are being made to introduce them from North America. 



