63 



and a complete record of this and all the subsequent stages is possible. 

 Owing to its small size it is easily portable and convenient for use in 

 the tropics. 



Nedergaard (N.). Malaria in Eastern Cuba. — Amer. Jl. Trop. Med., 

 Baltimore, Md., i, no. 6, November 1921, pp. 381-388, 2 figs. 



Most of the population of Cuba lives in towns, and shows a much 

 lower percentage of malarial infection than that of Jamaica, which 

 is largely employed on work in close proximity to pools, swamps and 

 sluggish streams where Anophelines abound. The economic aspect 

 of the malaria situation on the plantations of Eastern Cuba needs 

 further attention. Buildings and quarters for labourers should 

 be chosen and constructed under the approval of a sanitary expert, 

 for the actual cost of inefficiency and losses due to malaria is much 

 greater than the cost of efficient prevention. 



Cross (H. E.) & Patel (P. G.). A Note on the Transmission of 



Surra by Ticks. — Punjab Dept. Agric, Lahore, Vet. Bull. no. 6, 

 1921, 3 pp. [Received 10th January 1922.] 



All investigations regarding the transmission of surra have hitherto 

 been carried out with a few species of Tabanids, Stomoxys calcitrans,. 

 and fleas. Investigations led the authors to conclude that some 

 Arthropod that can survive for over a year might also act as a vector. 

 It was noticed that outbreaks of surra often occur at intervals in the 

 same district and stables, apparently without any introduction of the 

 disease into that district ; and in one outbreak the disease first 

 appeared among ponies that were healthy and had come from a 

 surra-free area, and that were placed in a stable that had not been 

 used for two years. 



Only one tick of the genus Ornithodorus was known in the Punjab, 

 namely, 0. lahorensis. During the present investigations a new and 

 allied species, 0. crossi, Brumpt, was found ; this species was found in 

 large numbers in the Murree hills. Many experiments in transmission 

 of surra by the agency of this tick are recorded in detail ; it was 

 found that the ticks transmitted the disease to a healthy rabbit 

 67, 83 and 101 days after feeding on an infected animal, but were 

 not infective after intervals of one minute to 46 days. This would 

 indicate that there is a life-cycle of the trypanosome within the tick. 

 How long the tick can remain infective, what changes take place in 

 the life-cycle of the trypanosome within the tick, and the minimum 

 number of ticks necessary to transmit the disease have not yet been 

 determined ; neither is it known whether other species of ticks are 

 capable of acting as vectors. The foregoing facts explain, however, 

 why surra breaks out yearly or periodically in the same stables and in 

 the same districts without any known importation of the disease. 

 The fact that the disease appears during hot and rainy months may be 

 due to the fact that many species of ticks hibernate during the cold 

 months and become active in the hot and rainy season, the disease 

 being rapidly disseminated among animals during this season by 

 Tabanids. 



East Coast Fever and its Eradication. — //. Dept. Agric. Union S. 

 Africa, Pretoria, iii, no. 6, December 1921, pp. 515-521. 



The position with regard to African Coast fever, particularly in 

 Natal and the Transvaal, is very serious. An account is given of the 



