411 



results of the current experiments will be published in a later paper. 

 Experiments in the introduction of fungous diseases of the white grub 

 have given variable results. 



The worst sugar-cane pest of the Island is Laclmosterna. vandimi, of 

 which the life-history and habits are described. In a small district one 

 sugar company collected in two years 4,723,000 beetles and 4,087,000 

 grubs at a cost of about £1 ,'200. The life-cycle of this species covers only 

 one year, and the beetles may be found from February to November, 

 the broods overlapping to such an extent as to distribute the emergence 

 of adults over all of the summer months. Nine months are spent 

 below ground in the larval stage, during which time the grubs are 

 feeding upon the roots of the sugar-cane. Hand-picking is largely 

 resorted to, hundreds of bushels of the grubs being collected in ploughed 

 fields in the day-time and of the beetles on cane foliage at night. 



L. vmidinei is confined to the western third of the Island. The adult 

 is a very general feeder, Casuarina and Poinciana regia (flamboyant) 

 being specially subject to attack, while bananas and coconut palms 

 often suffer severely, and sugar-cane leaves are also readily eaten. 



Paddock (F. B.). The San Jos6 Scale. — Texas Agric. Expt. Sta., 

 College Station, Circular no. 18, December 1916, 11 pp., 3 figs. 

 [Received 11th July 1917.] 



This paper gives a popular account of Aspidiotus perniciosus, with 

 recommendations for spraying and formulae for lime-sulphur solutions. 



BiLSiNG (S. W.). The Green Bug or Spring Grain Aphis {Toxoptera 

 gramimim, Rond.). — Texas Agric. Expt. Sta., College Station, 

 Circular no. 13, March 1916, 8 pp. 2 figs. [Received 11th July 

 1917.] 



Toxoptera graminum, Rond., is able to perpetuate itself throughout 

 the year in Texas owing to the variety of its food-plants. It is generally 

 supposed that dry, hot summers are unfavourable to its increase ; 

 heavy rainfall seems to be an efficient factor in control, but cold weather 

 seems to have but little influence on its numbers. Early-sown wheat 

 affords good protection for the Aphids and should be avoided whenever 

 possible. All self-sown wheat and oats in the early part of the season 

 should be destroyed. When only wingless females occur, the damage 

 is at first confined to circular areas, which turn yellow in colour. As 

 the insects become more numerous, they radiate out in all directions, 

 constantly increasing the size of the damaged area. When these areas 

 are first noticed they should be covered with straw and burned ; or 

 if this is not possible, they should be jjloughed and harrowed. The 

 wheat aphis is ordinarily kept under control by a small Braconid 

 parasite, Lgsiphlehus testaceipes, Cress. ; this parasite is active only 

 when the temperature is above 56° F. , while the Aphid is active at 

 40° F., and it is when the temperature is such that the Aphid increases 

 rapidly, while the parasite is unable to multiply, that a serious outbreak 

 occurs. 



