ENTOMOLOGY 5^1 



Journ. Med. Res., 9, 132-62) enumerates a number of cases 

 of myiasis in India and Persia describing the larvae, puparia, 

 and imagines of several of the insects concerned. Students 

 of Diptera will be interested in an excellent paper on the larva 

 of Chaoborus crystallinus (de G.) ( = Corethra plumicornis F.) 

 by S. C. Akehurst {Journ. Roy. Micros. Soc, 1922, 341-72), 

 The discovery of vestigeal thoracic limbs and ten pairs of 

 spiracular rudiments is of particular interest, these and other 

 features being survivals of a former terrestrial life. The gas 

 contained in the tracheal reservoirs is probably secreted by 

 the cells contained in tubes arising from the valve ends of 

 those four sacs. The author, unlike the physiologist Krogh, 

 is inclined to think that the integument is impervious and 

 consequently takes no part in respiration — a view which is 

 held by Frankenberg. W. B. Cartwright {Can. Eni., 54, 

 154-5) records a new example of " assembling," the species 

 concerned being the Hessian fly. Females were confined in cages 

 placed in the field, and on an average 145 males were attracted 

 per 25 confined females ; in one instance a single female 

 attracted 165 males, G. H. Carpenter and his collaborators 

 {Journ. Dept. Agric. Ireland, 20, No, 4 ; 22, No. i) contribute 

 the Fifth and Sixth Reports of their experiments and observa- 

 tions as to the life-history and treatment of Warble flies. 

 In the Fifth Report it is demonstrated that the insect can be 

 exterminated from an isolated area (Clare Island) by the syste- 

 matic squeezing out and destruction of the larvae from cattle. 

 By persevering efforts, extending over seven months a year for 

 six years, the cattle (about 450 in number) were rendered 

 altogether free. In the Sixth Report it is shown that all 

 results so far obtained indicate that the destruction of the 

 adult larvae by dressing the backs of cattle in spring is the 

 most effective method of combating the pest. It is hoped 

 that a wash of tobacco powder and lime, or some modification 

 of it, will form an effective and safe remedy on a large scale. 

 W. Bischoff {Arch. Naturg., Ill, 1-50, 51-60) discusses the 

 formation of the head in Dipterous larvae. D. L. Van Dine 

 {Bull. 1098, U.S. Dept. of Agric.) deals with the effect of 

 impounding streams and converting swamp-like areas to lake- 

 like conditions as a means of controlling the breeding of 

 mosquito larvae. After vegetation had been cleared away 

 and provision made for a sufficiently high level of water, the 

 method was considered successful. The non-breeding of 

 Anopheles in the impounded water requires further investi- 

 gation. 



Hemiptera. — P. Marchal {Compt. Rend., 174, 109 1-6) 

 gives an account of the metamorphoses of the " ground pearls " 

 Neomargarodes irabuti, from Algiers. The female is neotaenic 



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