^^ 1^^ MAY 1 G i92i 



CoTTERELL ^G. S). The Life-history and Habits of the Yellow Dung 

 fly {Scafophaga sterconvia) ; a possible Blow-fly ' Check.^—i?;'C)c. 



Zool. Soc, London, 1920, pt. 4, December 1920;''pp.:'.^,29-6<i7-r' 

 14 figs. 



In a preface to this paper Prof. Lefroy states that Scafophaga 

 stercoraria preys on a large number of Diptera, especially Calliphora 

 and Mnsca. [According to Major E. E. Austen, D.S.O., the statement 

 that Scutophaga normally attacks such large flies as Calliphora is 

 open to serious doubt. — Ed.] 



The author describes the various stages of this fly. It is wideh^ dis- 

 tributed, both in temperate and sub-tropical countries, having" been 

 recorded as far north as Nova Zemblya and Siberia, and as far south as 

 the Canary Islands and South Africa, but apparently is not known 

 from India or Australia. 



The eggs are laid over the surface of excrement, in batches of from 

 10 to 80, and each female lays from 100 to 150 eggs. Although any 

 excrement will serve as a breeding medium, sheep and cattle dung is 

 preferred for oviposition. The eggs hatch in from one to two days, 

 according to the temperature. There are three larval instars, the total 

 larval life lasting on an average 11 days, but this is governed by the 

 temperature and condition of breeding medium, the minimum time 

 observed being 8 days and the maximum 14 days. The pupal 

 stage lasts from 10 to 17 days, with a minimum of 6 and a maximum 

 of 18 days. The minimum period from adult to adult was 17 days, 

 and the maximum 31 days, with an average of 24 days. The life-cycle 

 from egg to egg takes from six to seven weeks. There are probably 

 five broods a year. Breeding continues from April to October. No 

 definite information has yet been obtained with regard to hibernation, 

 which probably takes place in the adult stage. In the field the fly 

 that is mainly attacked appears to be Borborus equinus, but it is 

 probable that all Diptera are preyed upon except Syrphids and 

 Stratiomyids, which are too active on the wing. Its method of 

 attacking its prey is described. The only natural enemy observed 

 w^as an unidentified Ichneumonid. 



Lassalle (C. F.). Report on an Anopheles Survey of the Colony of 

 Trinidad and Tobago.— Co/mr/7 Papers nos. S9 and 129 of 1920, 

 Port of Spain, 1920, 218 pp., 5 charts, 2 maps. 



The mosquito surveys of various districts of the Colony of Trinidad 

 and Tobago, begun in March 1914, had to be temporarily suspended, 

 and were only resumed in July 1917. The work is now completed, 

 and the reports from each district are given. The breeding areas are 

 described. The remedial measures advocated are based on the 

 measures adopted in the Panama Canal Zone. It may be impossible 

 to eradicate every breeding place throughout the colony, but those 

 within and for a certain distance around all towns, villages, estates 

 and other centres of population should be effectively dealt with. 



In the second part of this report lists of mosquito breeding places 

 are given, arranged under the various districts. A complete list of 

 the Trinidad mosquitos is also appended [R. A.E., B, v, 59, 60]. 



Brunetti (E.). Catalogue of Oriental and South Asiatic Nemocera 



Rec. Ind. Mus., Calcutta, xvii, June 1920, 300 pp. [Received 

 28th January 1921.] 

 Mosquitos include a large portion of the species in this catalogue, 

 which incorporates all available names up to about the middle of 1919. 



(2434) W't. P.3, 164 1500 4,21 Harrow G.75-3 F 



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