156 



Under certain c'rcumstances the arsenious oxide in the arsenite 

 of dips tends to change into another form producing arsenate [R.A.E., 

 B, viii, 6, etc.]. This has about half the tick-killing power of arsenite, 

 has a scalding and poisoning effect on cattle, and is not apparent 

 in the test described. The proportion of arsenate tends to increase in 

 a tank that has stood unused for some time. 



HiNE (J. S.). Descriptions of Horseflies from Middle America. I. — 



Ohio Jl. Sci., Columhis, xx, no. 6, April 1920, pp. 185-192. 

 [Received 7th July 1920.] 



The following new Tabanids are described: — Tabanus fulmineus and 

 T.festivus, from the Canal Zone ; T. murreus, T. modicus and T. tantalus, 

 from British Guiana ; T. umbratus and T. validus, from Costa Rica ; 

 T. mordax, from Paraguay ; T. furvus from Bolivia ; T. curtus from 

 Venezuela ; T. bruesi, T. lautus and T. ^mnensis, from Peru ; T. tacitus 

 from Uruguay, T. trivittatus, ¥., from British Guiana is redescribed. 

 These are all placed in the genus Tabamts {sens, lat.) to avoid the 

 erection of a number of new genera, a procedure that is considered 

 undesirable at present. A key to the new species is also given. 



It is proposed to substitute Stichocera, n. n., for Dicrania and 

 Dicranomyia, both of which have been used for the same genus and are 

 preoccupied. 



Edwards (F. W.). The Nomenclature of the Parts of the Male 

 Hypopygium of Diptera Nematocera, with special reference to 

 Mosquitos. — Ann. Trojp. Med. Parasit., Liverpool, xiv, no. 1, 

 30th June 1920, pp. 23-40, 2 figs. 



The contents of this paper are sufficiently indicated by the title. 



Macfie (J. W. S.). Heat and Stegomyia fasciata : Short Exposures 

 to raised Temperatures. — Ann. Trop. Med. Parasit., Liverpool, xiv. 

 no. 1, 30th June 1920, pp. 73-82. 



As a result of these experiments it was found that the ability of 

 Stegomyia fasciata to withstand sudden exposure for five minutes to a 

 raised temperature is greatest in the egg-stage, slightly less in the 

 pupal stage, and least in the larval and adult stages. It was also 

 found that the effect of heat varied greatly as a result of the manner 

 in which it was applied, the length of time occupied in reaching the 

 particular temperature, and the length of time that temperature was 

 maintained. During the observations here described only exposures 

 of 5 minutes were studied. 



Adult mosquitos are apparently more susceptible to the action of a 

 raised temperature in the absence of moisture. 



Blacklock (B.) & Carter (H. F.). - On the Results obtained from 

 Surveys for Breeding-Places of Tree-Hole Mosquitoes in Liverpool 

 and Neighbourhood.^ — Ann. Trop. Med. Parasit., Liverpool, xiv, 

 no. 1, 30th Jmie 1920, pp. 115-126, 1 fig., 1 plate. 



The results of a survey to determine the frequency with which 

 breeding places of Anopheles plumbeus, Steph., occur in trees are 

 summarised by the authors as follows : — ^In a series of 6 surveys, 5 iu 



