13 t KICVIKW TUOnCAL JI]'',I1ICINE, ETC. 



Mosquitoes Felt,' in a somewhat similar report on the mosquitoes of New York State, describes 



— coiUitiual the fungus diseases attacking mosquitoes. Tliose arc Entoinu-phthora spmrusyerma (Fersn.), 



wliioh attacks other insects as well, Empnsa culicis (Braun), like the fungus of house-flies, 



and, possibly, Enipitsn pupilata. A new species of Entoimfphthora has also been described. 



Attempts made to spread the disease caused by it failed. 



McWeeney- deals with Schaudinn's work. The latter investigated the ojsophageal 

 diverticula of Cnlcx pipiens. 



These become distended with gas and may be termed " gas-bags." The gas is carbon dioxide which is evolved 

 by a sort of ycast-like fungus always present in the insect's stomach from traces of glucose present in blood, 

 or — much more abundantly — from glucose present in the plant juices which the insect occasionally sucks. At the 

 commcucemont of the act of suction, when the insect has its proboscis buried in the skin of its victim, its Ijody 

 undergoes one or more violent contractions which eject the contents of its foregut and " gas bags " into the 

 skin. These contents comprise gas, saliva and whatever particulate matter is present — viz., yeast cells and 

 sporozoites. Schaudiun looks upon this contraction as a sort of dyspnceal effort due to the entrance into its 

 trachae of the CO.^-laden air which bathes the skin. He succeeded in producing the contraction artificially by 

 placing an infected culex on a cupped slide, with its proboscis in a drop of glycerin under a cover-glass, and 

 its body projecting over the hollow. In this he evolved some C0„ from a fragment of chalk and a droplet of 

 acid, and he observed that the gnat's body underwent a violent contraction, which had the effect of expelling 

 into the glycerin its contained gas, yeast cells and sporozoites. Viewed teleologically , the effect of the injected CO.^ 

 would be to paralyse the thrombocytes and in other ways to delay the coagulation of the blood. I'hc hyper- 

 emia and pain caused by the l)ite he considers to be due to the enzyme of the yeast cells. He dissected out 

 the "gas-l)ags" and pushed them into a fine puncture in his own skin, with the result that the typical 

 swelling, redness, and itching came on at once. The salivary glands he found quite inoperative. The effect 

 of the " gas-bags " appears to dei)end on the quantity of yeast cells contained in them, for it was much more 

 marked when the yeast had been allowed to proliferate actively as the result of feeding the gnat on plant 

 juice. The fungus is not a true yeast, but a yeast-like stage in the life-history of one of the Entomophlhorv:, 

 fungi with which we are all acquainted in the shape of the well-known Enipusa lamav, which kills flies in the 

 fall of the year and causes their bodies to adhere to the window pane surrounded by a white cloud of ejected 

 conidia. 



In view of the discovery of a new species of Sudan mosquito, C. salnn, breeding in 

 sea-water, the observations of Foley and Yvurnault^ are of interest. They found in Algeria 

 that an anopheline, Fijrctophonis chandoijei, was able to breed out in very saline waters. 

 The same, they note, as being true of Anopheles vayus found in the Dutch East Indies. 



Some notes on applications for allaying the pain of mosquito bites may be useful. 

 A mixture one has seen highly recommended consists of a half-pint 1 in 20 carbolic acid 

 and 4 oz. No. 4711 Eau de cologne. 



Schill-** advises applying a paste or saturated solution of bicarbonate of sodium to the 

 bitten part ; while as a repellent, 50 per cent, alcoholic solution of thymol may be tried. 



Joly's mixture is as follows : — 



Liq. formaldehyd (40 per cent.), 5 iv. 



Xylol, 5 iss. 



Acetoni, 5 i. 



Balsam-canaden., gr. xv. 



01. citronelliE, q.s. 



Before applying, shake the mixture and touch the bitten part with the end of the 

 wetted cork or small piece of cotton wool, and then allow the fluid to dry on the skin. 



As regards measures for destroying the imagines, one has been accustomed to use the 

 sulphur squibs advocated by Giles, '^ but they merely stupefy the insects which have 

 afterwards to be killed. An Indian remedy consists of a tablespoonful of potassium 

 nitrate 1 part, powdered chrysanthemum 4 parts, and powdered nard root {Nanlus indica, 

 or Spikenard) 4 parts. 



» Pelt, E. P., " Mosquitoes or Culivida: of New York State." Albany, 1904. 



" McWeeney, E. J. (March 25th, 1905), " On the Relation of the Parasitic Protozoa to Each Other and to 

 Human Disease." Lancet, Vo\. I. 



" Foley, F. H., and Yveruault, A. (March 11th, 1908), " Anophelinos dans d'eau Salee." Bull. Soc. Path. 

 Exol., Vol. I. 



■• Schill, " Mosquito Bites." Quoted in Journal of Tropical Medicine, November 1st, 190G, Vol. IX. 



^ Giles, Q. C, " Gnats or Mosquitoes." London, 1902, 



• Article not consulted in the original. 



