133 



Only in parts occupied by Europeans is the work of combating its 

 spread carried out with any thoroughness. Inoculation operations 

 have decreased in number ; in the opinion of the author, this form of 

 treatment should be entirely replaced by dipping. 



The life-history of Psoroptes communis (sheep scab parasite) has 

 been investigated. The maxinnim length of time that a female example 

 lived on a sheep was 40 days. The eggs hatched in 48 hours when 

 in direct contact with the skin of a sheep ; when placed on top of a 

 thick crust, they remained from 3 to 4 days without hatching ; when 

 placed in the wool 6-8 days was required. Eggs kept for 10 days 

 away from a sheep, failed to hatch when returned to the normal host ; 

 similarly eggs stored in moist sheep faeces for 13 days did not hatch 

 when returned to the sheep. Eggs could not stand exposure to 

 sunlight. The larvae transformed into nymphs 4 or 5 days after 

 hatching ; when removed from a sheep the larvae Uved 2 or 3 days. 

 The nymphs became mature on the 5th day ; pairing occurred on 

 the 6th day at Pietermaritzburg and on the 7th and 8th days at 

 Onderstepoort. Egg-laying began 9 or 10 days after hatching. 



Experiments were conducted in Natal to test the efficiency of a more 

 dilute arsenical dip against ticks infecting working oxen. No definite 

 conclusion had been reached at the end of 1913. 



Hewitt (C. G.). House-Fly Control.— y4^nV. Gaz. Canada, Ottawa, ii, 

 no. 5, May 1915, pp. 418-421. 



These notes are primarily intended as a guide in planning anti-fly 

 campaigns. Stress is laid on the necessity of undertaking control 

 work early in the season. Eules for the prevention of breeding and 

 of infection are given, and it is pointed out that education is the most 

 important factor in the campaign. The attitude which regards health 

 as a civic asset, will enable proper sanitary legislation to be enacted. 

 Horse manure is the chief breeding place of the house-fly, and in dealing 

 w4th the rural problem it is noted that storing manure reduces its 

 manurial value, and that the most effective insecticidal substance for 

 manure is borax in the commercial form, used either dry or in solution 

 [see this Revieiv, Ser. B, ii, p. 178]. 



Oliveira (M. R. de). Carracas. [Ticks.]— 5o'e.'m de Agricultura, Depart. 

 Agric. Prov. de Mo^'ambique, Lourenco Marques, nos. 1-3, January- 

 March 1915, pp. 43-50, 3 plates. [Received 3rd August 1915.]' 



This is a general account of ticks, the damage done by them and 

 the methods best adapted for controlling them. The author divides 

 ticks into three groups, according as they require one, two or three 

 hosts for the completion of their life-cycle. As examples of each 

 group, Amblyomma hebraeum, Rhipicephalus evertsi and Margaropvs 

 annulatus var. decoloratus are described and figured, and an account 

 of their hfe-history is given. The necessity for systematic dipping 

 and the possibility of practically ridding the country of a pest which 

 causes great loss to cattle-owners is emphasised. It is suggested that 

 the introduction of foreign cattle should be prevented. 



