226 VENOMOUS ANIMALS: PROTOZOA TO ARTHROPODA 



Symptoms. — Shortly after a mosquito has bitten a person, a 

 sensation of itching is experienced in the affected part, which on 

 examination is seen to be inflamed and reddish, while a wheal not 

 unusually develops, especially in persons new to the tropics. Some- 

 times a papule or even a nodule may iorm on the site of the bite, 

 while more rarely scratching leads to secondary infection and the 

 formation of boils, lymphangitis, or lymphadenitis. 



Treatment. — The itching may be relieved by dilute solutions of 

 ammonia (Scrubb's Ammonia is a favourite remedy), or by a 5 per 

 cent, solution of carbolic acid, or i per cent, alcoholic lotion of 

 menthol. Inflamed bites may be cleaned with i in 40 carbolic 

 lotion, and afterwards dressed with boracic ointment. Local septic 

 poisoning should be treated by boracic or carbolic fomentations, 

 while boils and abscesses must be opened. 



Prophylaxis. — ^The prevention of mosquito-bites will be discussed 

 in the chapter on Malaria (Chapter XL.). 



Other Diptera. — ^Numerous flies other than the Culicidse cause 

 irritation by their bites, such as fleas, but the nature of the venom 

 not being well known, they will be considered together in Chapters 

 XXXIL, p. 771, XXXilL, p. 814, and XXXIV., p. 857. 



In Cape Colony there is a superstition that the * bee moth ' — 

 i.e., death's-head moth, Acherontia atropos Linnaeus — is poisonous. 

 This is not so. 



6. Coleoptera. 



Beetles and their larvae are capable of inflicting severe bites or 

 wounds by means of stiff hairs. Silvanus surinamensis L., the 

 saw-toothed grain-beetle, is said to bite people. Wellman describes 

 the larva of a beetle, which the natives of Angola call ' ochisia,' 

 which means ' to be left alone,' whose bristles will even penetrate 

 the skin of the sole of the foot, causing pain, inflammation, and 

 even sloughing, when trodden upon. 



Blister Beetles. — Chalmers and King in 191 7 have drawn 

 attention to the beetles Epicauta sapphirina Maeklin, 1845, and 

 Epicautat omentosa Maeklin, 1845, as the cause of ' seasonal vesic- 

 ular dermatitis ' in Khartoum, while P. H. Ross had studied in 

 19 1 6 the same complaint in Nairobi, where it was caused by Pcederus 

 crihipunctata Epp {sic), and P. da Silva had traced in 1912 similar 

 outbreaks in Brazil to Pcederus columbinus de Laporte, 1832; Eysell 

 to Feeder us peregrinus Fabricius, 1801, in Malaysia; and Rodhain 

 and Houssian to a species of the genus Pcederus Fabricius, 1775 • 

 Finally, Roubaud has stated that Epicauta flavicornis Dujardin, 

 1838, is the cause of the same complaint in Senegal. 



The whole subject, however, belongs to Chapter XCVL, the 

 Dermatozoiases, and is only mentioned here foi the purposes of 

 reference. 



It will be noted that the various authors only mention two 

 genera — viz., Epicauta Dejean, 1803, which belongs to the family 

 CantharidcB Leach, 1817, and Pcederus Fabricius, 1775, belong- 

 ing to the family Staphylinidce, which latter lack the appendage 



