f 



157 



for half an hour at 12° C. (54° F.) in a soap solution containing 2 per 

 cent, of trichlorethylene or 10 per cent, of tetrachlorethane is effective. 

 Steeping for half an hour in a 5 per cent, solution of cyllin in water 

 maintained at 65° C. (149° F.) is also effective on woollen articles. 

 For reasons of economy, the chlorine derivatives of ethane and ethylene 

 cannot be used at present in a dry-cleaning process, but their soap 

 preparations are of value. Petrol has a wide application and is readily 

 obtained. For cleansing the body itself, bathing or sponging with 

 soap solutions containing 2 per cent, of trichlorethylene or 10 per cent, 

 tetrachlorethane gives the best results. In view of the known 

 insecticidal action of these chlorine derivatives of ethylene and ethane, 

 it is probable that good results would be obtained by shampooing 

 verminous heads with their soap preparations and it is also probable 

 that a 25 per cent, solution of trichlorethylene in vaseline would form 

 an efficient insecticidal ointment. It is almost certain that hce would 

 not continue to live on the human body if anointed daily with a 25 

 per cent, solution of trichlorethylene in vaseline or on the body anointed 

 twice daily with a solution of petrol in vaseline of similar strength. 

 The odour of such an ointment is not unpleasant, but when living under 

 verminous conditions, constant precautions would have to be taken 

 and every method of destroying vermin would require to be employed. 

 Any attempt to render an army free from vermin in war time would 

 require that all men occupying the same quarters at the same time, or 

 for alternating short periods of time, should be regarded as a single 

 unit for which a receiving station with cleansing apparatus should be 

 provided. Such an attempt would also require that the movements of 

 the men of! duty were controlled, and this would be limited by military 

 necessities. 



Bodkin (G. E.). Report of the Economic Biologist.— J?ej9^ Be'pt. 

 Science and Agric, British Guiana, 1913-1914, Georgetown, 

 30th April 1914, 11 pp. [Received 24th July 1915.] 



During the year mal de caderas appeared among mules on a number 

 of sugar plantations, resulting in a heavy mortality. As the disease 

 is popularly supposed to be insect-transmitted, investigations were 

 made in the infected areas. Instructions were given as to the pre- 

 paration of a suitable fly repellent with which animals on infected 

 plantations were to be dressed. Several species may be responsible 

 for the spread of the disease, assuming it to be thus transmitted. 

 These, in order of prevalence, were : Stomoxys calcitrans, L., Tahanus 

 trilineatus, Latr., T. semisordidus,Wa\k., T. impressus,Wied., T.desertus, 

 Walk., T. caiennensis, F., Chrysops tristis, F., and C. costata, F. 



Report of the Veterinary Committee. — Rept. Dept. Science and Agric., 

 British Guiana, 1913-1914, Georgetown, 30th April 1914, pp. 11-14. 

 [Received 24th July 1915.] 



Mal de caderas is prevalent in the counties of Demerara and 

 Berbice, and quarantine restrictions have been placed on infected 

 districts. The precautions recommended include isolation of infected 

 animals ; cleaning stables with kerosene or chloro-naphtholeum and 

 subsequent lime-w^ashing, the wash containing 5 per cent, crude 



