90 



water, into hoof-prints, etc., and will float in among plants or otiisr 

 obstructions on the surface, provided they do not form a complete 

 canopy. A remarkably small quantity of this material will kill 

 Anopheline larvae if properly applied, and since it costs from about 

 10 pence to 15 pence per gallon in bulk, and 1 gal. will do the work 

 of several gallons of oil, its use would effect a substantial economy. 

 As creosote is poisonous to fish and other animals, it must be used 

 with caution on water containing fish, or used by stock. 



Useful equipment and supplies include dynamite for removing 

 stumps from ditch lines, etc., horse-and mule-drawn ditching machines 

 for makmg V-shaped ditches of less than 3-ft. depth in open land, 

 and phosphate drags, tools somewhat resembling a potato fork but 

 more substantial, which are invaluable for cleaning out ditches or 

 for working in marshy land that is full of obstructions such as roots. 



Saundees (P. T.). Douchage pour la Destruction des Tiques h Antigues. 



[Dipping for the Destruction of Ticks at Antigua.] — Sta. Agron. 

 Guadeloupe, Pointe-d-Pitre, Antilles Francaises, Bull. no. 1, 1919, 

 pp. 31-35. 



Ticks have been for some years a serious drawback to the raising 

 of cattle in the French Antilles, very little having been done in many 

 of the Islands to combat them. The usual method has been to remove 

 the ticks by hand or with a knife, after which the infested parts are 

 rubbed with a weak solution of disinfectant liquid. This method 

 has left much to be desired ; it cannot be thorough in practice, while 

 in the case of Amhlyomma variegatum the mouth-parts of the ticks 

 remain in the skin of the host when the tick is removed and frequently 

 cause a poisoned wound. The establishment of a dipping apparatus 

 has resulted, after 12 months' use, in a great improvement in the 

 condition of the cattle, and it is suggested that horses and mules 

 might with advantage be treated in the same way. Particulars are 

 given of one of the standard types of dipping apparatus. 



Headlee (T. J.). Practical Application of the Methods recently 

 discovered for the Control of the Sprinkling Sewage Filter Fly 

 {Psychoda alternata). — Jl. Econ. Entom., Concord, N.H., xii, no. 1, 

 February 1919, pp. 35-41, 2 plates, 4 figs. 



An account of the fly, Psychoda alternata, occurring in sprinkling 

 sewage filters, and the discovery of the possibility of controlling it 

 by submerging the larvae and pupae in water for 24 hours, has recently 

 been noticed [see this Review, Ser. B, vii, p. 24]. It is not known 

 whether the flies are actual carriers of disease, but as they fly, or are 

 wind borne, into houses at a distance of J mile from the sewage filters, 

 and there penetrate the finest screens and fall into food that is to be 

 eaten by human beings, the probability is that infection is brought 

 by them. The first experimental submergence having resulted in 

 the destruction of 100 per cent, of the larvae and pupae, a large 

 sewage disposal plant was fitted with a bulkhead pierced with a passage 



ay that could be opened or closed, one bulkhead being installed in 



