146 



place seems to be the amount of use to which the dip is put, and appa- 

 rently only in those dips through which large numbers of cattle are 

 passed at very frequent intervals will reduction, that is to say, an 

 increase of the proportion of arsenite to arsenate, take place ; this 

 occurs in some of the large stock-yard centres. 



The necessity for knowing more or less accurately, at any required 

 time, the precise chemical state of the dip is thus apparent, and the 

 author thinks that this may be determined by modifications of labora- 

 tory methods, which in his opinion could be made use of by persons 

 possessing only a limited chemical training. He describes in detail 

 processes which may be used {a) by trained chemists, (6) by persona 

 having only a slight chemical knowledge, and (c) by persons in the 

 field possessing no chemical knowledge whatsoever, but who obtain 

 results by strictly carrying out the manipulations of the ** outfit " 

 prepared by a trained chemist. 



The process for the determination of arsenious acid and also the 

 total arsenic actually present is described at length ; the field outfit 

 is figm^ed and directions given for its use. It is not pretended that 

 these field methods will give laboratory results, but, if carefully used, 

 the author feels sure that the owner of the dip will be able to ascertain 

 its condition with sufficient accuracy for the purpose. 



Bandermann (F.). Die Vernichtung der Stechmticken und ihre 

 Folgen. [Mosquito destruction and its results.] — Entom. Zeitschr., 

 Frankfurt a. M., xxviii, no. 1, 4th April 1914, p. 3. 



The author states that the mosquito campaign instituted by the 

 German authorities will probably upset the natural balance of insect 

 life in Germany. In villages around Halle a.d. S. cellars have been 

 lime-washed or fumigated with sulphur, and the rigorous enforcement 

 of these measures makes it impossible to find a single insect of any 

 kind in hundreds of cellars visited by the author in his official capacity. 



MiESSNER (H.). Zahlreiche todliche Erkrankungen beim Rinde durch 

 Simuliumstiche und Nachweis des Puppenstadiums dieser Mttcken. 



[ISumerous deaths among cattle caused by Simulmm bites and 

 the investigation of the pupal stage of these flies.] — Deutsche 

 Tierdrztl. Wochenschr., Hannover, xxii, no. 18, 2nd May 1914, 

 pp. 281-282. 



In previous years few deaths among cattle in the Leine district 

 have occurred from sandfly-bite, but this year there were many fatal 

 cases. This abnormal mortahty was due to the great increase in the 

 number of flies. At the beginning of 1914, many districts in the 

 vicinity of the river Leine were flooded, favouring the development 

 of the early stages. Early in April, great heat caused the floods to 

 recede and the Simulium emerged in swarms. The flies are usually 

 found on the low ground by the Leine, but the wind prevaihng on the 

 19th and 20th of April blew them from the river to the pasture land 

 and the largest number of deaths occurred on the 20th and 21st of 

 April. About 40 beasts are said to have perished within some 2| 

 miles of the river-banks. The author thinks that the epidemic will. 



