47 



the flagellates represented. It is probable that all the infections 

 of the proboscis were T. mvax, those of the gut and salivary glands 

 were possibly T. pecaudi {T. brucei of Uganda), as were also, perhaps, 

 those of the gut only, though, according to Roubaud, T. jpecaudi 

 develops in the gut and proboscis and not in the gut and salivary 

 glands. None of the infections resembled stages of the development 

 of T. congolense. 



A bibliography of four references is given. 



Macfie (J. W. Scott). Chlorine as a Larvicide. — Rejjt. Accra Labora- 

 tory for the Year 1915, London [n. d.], p. 71. [Received 23rd 

 January 1917.] 



Experiments were carried out to test the effect of free chlorine 

 dissolved in water as a larvicide. Fifty larvae of Stegomyia fasciata 

 were introduced into samples of clear tap water and water containing 

 mud, weed, etc., in which larvae were actually found breeding, 100 oz. 

 being used in each case. Two drachms of chlorine solution (1 : 550) 

 were added, giving a proportion of approximately 1 in 250,000. 

 The larvae remained unaffected in both tap water and their natural 

 medium when the chlorine was present in this proportion, as also 

 when it was raised to 1 in 62,500, 1 in 50,000 and 1 in 25,000, 

 but at 1 in 10,000 all the larvae in the tap water and a few of those 

 in their natural medium were dead at the end of two hours, while 

 all were dead within 24 hours. Some Cyclops present in their natural 

 medium were also killed. Chlorine would not, therefore, appear to 

 be of practical use as a larvicide, even if it were possible to remove 

 the excess, after the larvae have been killed, by means of some suitable 

 antichlor, such as sodium thiosulphate. 



Macfie (J. W. Scott). Notes on the Insects collected at Accra during 

 the Year. — Rept. Accra Laboratory for the Year 1915, London, 

 [n. d.], pp. 76-79. [Received 23rd January 1917.] 



The number of mosquitos collected at Accra now totals 32 species. 

 Besides those already recorded [see this Revietv, Ser. B, v., p. 3] the 

 following are here mentioned : — Cidex ornatothoracis, Theo., C. quasi- 

 gelidus, Theo., C. thalassius, Theo., and C. thalassius vai. fuscus, Theo. 

 Many examples of Mansonioides africanus captured were infested with 

 little red mites. The commonest Anopheline mosquito is A. coslalis. 

 Specimens of Ochlerotatus irritans, Culexfatigans and C. decens sent to the 

 laboratory were found to be flourishing in media containing a high per- 

 centage of salt. The last-named was breeding in water actually more 

 salt than sea- water. They had been captured in crab-holes near a lagoon, 

 the water of which is brackish, and had, no doubt, become concentrated 

 by evaporation. The average of 30 estimations of the chlorine in 

 media in which this insect was foimd worked out at 4 '3 parts per 

 100,000, and the highest proportion observed was 20*5 parts. 



Other biting insects captured included : — Phlebotomus minutus, 

 Rond., var. africanus, Newst., P. (?) squamipleuris, Newst. ; Tabanus 

 ditaeniatus, Macq. ; Glossina palpalis, R.D., G. longipalpis, Wied., 

 Stomoxys calcitrans, L., Cordylobia anthropophaga, Griinb., from a 

 guineapig's foot; the fleas, Echidnophaga gallinacea, Westw., on 



