46 



Stomoxys calcitrans, Calliphora erythrocephala, C. vomitoria, Lucilia 

 caesar, PoJJenia riidis, Scatophaga sfercoraria, Glossina morsitans and 

 G. palpaJis. Emphasis is laid on the fact that an intimate and complete 

 knowledge of the life-history of noxious insects is essential if they are 

 to be controlled. 



Whitfield (A.)- Acarus from a Case of Copra Itch. — Proc. Roy. Soc. 

 Med., London (Dermat. Sect.), viii, no. 6, April 1915, p. 116. 



In connection with a case of copra itch in a stevedore in London, 

 the author obtained a specimen of Tyroglyplms Jongior, Gerv., var 

 cnstellunii. Hirst, from a sample of the copra [see this Revieiv, Ser. B, i, 

 pp. 15-16]. 



Bevan (LI. E. W.). Ticks and the Animal Diseases.— i2/?oc?e5ia Agric. 

 Jl., Salisbury, xii, no. 6, December 1915, pp. 766-784, 2 figs. 



Parasites introduced into domestic animals by means of ticks 

 produce their ill-effects in several ways : — (1) by interference with the 

 circulation of the blood ; (2) by the destmction of blood cells ; (3) by 

 robbing the host of food material ; and (4) by the production of 

 substances toxic to the host. Almost all cattle in Ehodesia become 

 infected by the blue tick [Margaropus decolomtus] with the parasites 

 of redwater and gall-sickness. If cattle are infected when young, they 

 usually become more or less immune, but always retain the parasites 

 in the blood. Older animals or imported cattle suffer more severely 

 when infected, and in a state of lowered vitality are attacked by minor 

 ailments such as scour, pneumonia and liver disease. The following 

 formula is given for a dipping fluid for use against the brown tick 

 [Rhipicephalus appendiculafus] : — 3 lb. soft soap, 1 lb. paraffin, 4 lb. 

 sodium arsenite (80 per cent, arsenic) and 400 gals, water. In severe 

 cases, in addition to regular dipping, a special dressing made of from 

 6 to 8 paraffin wax candles dissolved in a quart of paraffin should be 

 applied to the inside of the ears and other protected parts. In the 

 Beira districts, diseases of cattle caused by tsetse-flies are reported 

 to have been controlled by use of a dipping fluid. 



HoLBOROw (A. G.). Notes relating to Arsenical Dipping Fluids. — 

 Rhodesia Agric. Jl., Salisbury, xii. no. 6, December 1915, 

 pp. 785-788. 



The oxidation of arsenite of soda in dipping fluids is due to the 

 action of micro-organisms, the arsenate produced possessing about 

 lialf the tick-killing power of the original solution. Oxidation was 

 found to be slightly arrested by the constant dipping of cattle. In 

 three tanks near Salisbury, oxidation was shown to proceed rapidly 

 until from 15 to 20 per cent, of the arsenite had been changed. The 

 process was then reversed, until finally only a small quantity of arsenate 

 was present. About 500 head of cattle were dipped in the tanks every 

 week. There appears to be no fixed rate of oxidation which can be 

 applied to all dipping fluids. An isometer can be used to determine 

 the arsenite present, but leaves the arsenate unrecorded. In a 

 Rhodesian tank, under average conditions, the fluid should be changed 

 about every six months. 



