133 



CoorER (W. F.) v.^ Laws (H. Iv). The Tick-killing- Properties of 

 Sodium Arsenate. — Agric. .71. of the Union of SoutJi Africa, 

 V, uo. 5, May 1913, pp. TlG-721. 

 Experiments by A. Y. Fuller and others have established with- 

 out doubt that sodium arsenite becomes oxidised to sodium 

 arsenate in a cattle-dipping' bath, but the precise conditions which, 

 iniiuenee the rate ot oxidation are not yet known. At present it 

 is customary to consider sodium arsenite as the only tick-killing- 

 agent, and to regard the arsenate as useless. This conclusion 

 appears to be erroneous, because, in the first place, the tick-killing 

 value of a dip is not always proportionate to its arsenical content ; 

 and secondly, sodium arsenate has, according to special experi- 

 ments by the authors, about 40 to 50 per cent, of the tick-killing 

 eifect of the arsenite. The arsenate, therefore, certainly is a 

 factor to be reckoned with, and the only true test ot the activity 

 of a dip is to test it on tick-infested cattle, when it will be found 

 that even those dips which contain exactly the same quantity of 

 sodium arsenite as well as arsenate are not all equally effective. 



The Mahambanendhlwana. — Afjric. .11. of the J'nion of South. 

 Africa, V, no. 5, May 1913, p. 788. 

 In reply to a correspondent the Assistant Chief of the Division 

 of Entomology (Mr. C. Fuller) states that the aboriginal story, 

 generally accepted by Boer and British farmers, that cattle feed- 

 ing upon veld-inhabiting bag-worms or basket-worms (Zulu, 

 Mahambanendhlwana) [larvae of moths of the family Psychidae] 

 die from their poisonous effects is unsupported by facts. Twenty 

 to thirty of these insects were experimentally fed to an ox. 

 without anv ill effects . 



XiELSEX (Dr. J. C). On some South American Species of the Genus 

 Mydaea, Parasitic on Birds. — Vidensk. Meddel. fra Dansk 

 ■iiaturli. Foren., Ixv, 26th May 1913, pp. 251-256, 4 figs. 



In 1911 the author recorded a fly, Mydaea anomala, Jaeun., 

 from Concepcion, Argentina, the larvae of which develop as sub- 

 cutaneous parasites in tumors on various birds (Spermophila 

 gutturalis, Mimus modulator, Homorus lophotes, Pitangus sulfur- 

 atus holiviainis). Last year (1912) he received flies, puparia and 

 third stage larvae of another species of Mydaea which is parasitic 

 on Xiphocolaptes albicoUi.'^ in Argentina. This species proves to 

 be the true .1/. anotnaJa, and the fly described in 1911 is a new 

 species which Dr. Xielsen proposes to name M. torquens. 



Bruce (Sir D.), Harvey (Major D.), Hamertox (Major A. E.), 

 & Lady Bruce. Infectivity of Glossina morsitans in 

 Nyasaland. — Froc. Roy. Soc., London, B. Ixxxvi, uo. B. 589, 

 12th June 1913, pp. 422-426, 4 tables. 

 The authors, after experimenting with more than 10,000 tsetse- 

 flies {Glossina morsitans) caught in the ' proclaimed area ' of 



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