81 



Macdougall (E. S.). Insect and Arachnid Pests of 1916.— Keprint 

 from Trans. Highland & Agric. Soc. Scotlatid, 1917. pp. 1-10, 

 39 figs. 



Recommendations for the control of lice [Pediculus humanus] include 

 the use of the powder known as N.C.I, [see this Revieiv, Ser. B, jv, 

 p. 133] and of undervests of butter-muslin soaked in insecticide 

 solution [see this Revieiv, Ser. B, v, p. 91]. 



The mites causing itch, mange or scab such as Sarcoptes, Psoroptes 

 and Symbiotes {Chorioptes) are described, and a key to them is given. 

 Demodex follicidorum, the mite causing demodectic or follicular mange, 

 and Tromhidium holosericeum (harvest mite) are also dealt with. 



Dexler (G.). Observations on Certain Flies Infecting Meat and 

 Causing Human Myiasis. — Agric. Gaz. Canada, Ottawa, v, no. 1, 

 January 1918, p. 99. [Abstract from Zeitschrift fur Fleisch- und 

 Milchhjgiene, Berlin, Nov. 1st & 15th, & 1st Dec. 1916.] 



From observations on the adults, eggs, larvae and pupae of flies 

 that visit meat, carried out in the largest markets in Vienna, the 

 author concludes that flies prefer, both for feeding and for oviposition, 

 fresh meat at a temperature of at least 62° F., chilled or frozen meat 

 being avoided by them. The eggs are laid for preference in those parts 

 of the meat that are fairly damp, warm and not directly exposed to 

 sunlight, especially the abdominal cavity, lower part of the back, 

 muscle folds, etc. The species most frequently occurring on meat are 

 Lucilia sericata, Meig., Calliphora erythrocephala, Meig., Sarcophaga 

 haemorrhoidalis, Meig., S. nurus, Rond., S. falculata, Band., Phormia 

 groenlandica, Zett., Muscina stabulans, Fall., Fannia canicularis, L.^ 

 and F. scalaris, L. 



The following occur rarely on meat, on which they feed, but 

 never oviposit : — Ophyra leucostoma, Drosophila funebris, Musca 

 domestica, Calliphora vomitoria, Sarcophaga carnaria, Musca meridiana,. 

 and Stomoxys calcitrans, the presence of their larvae affording no 

 evidence as to whether the meat is putrid or not. The size of the 

 larvae in infected meat is practically of no use for determining the 

 length of infection. The exposure of infected meat to a temperature of 

 50° F. arrests the process of hatching and causes the eggs to die off, 

 while the larvae are killed by drying or by exposure to direct sunlight. 

 A temperature below 44 "6° F. arrests the development of the larvae, 

 but does not kill them, the optimum growth temperature being 

 between 68° and 104° F. The larva pupates on the fifth or sixth day 

 after hatching. 



Marchoux (E.). Influence du Milieu ext6rieur sur la Resistance de 

 I'Organisme au Paludisme. [Influence of Environment on the 

 Resistance of the Organism to Malaria.] — Bull. Soc. Path. Exot., 

 Paris, xi, no. 1, 9th January 1918, pp. 1-3. 



The author discusses the observations made by Lagriffoul and 

 Picard [see this Review, Ser. B, vi, p. 70] on the rarity of such cases of 

 mixed infections of malaria as were previously recorded by him. 

 Criticising the statement that malarial subjects who were favourably 



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