THE J'ENOM OF MOSOCITOES 453 



THE VENOM OF MOSQUITOES. 



The females only (Ciilicid^e) attack man. 



The mandibles and maxilla? pierce and cut like spear points and 

 saws. 



An irritating substance is injected from the salivary glands, the 

 nature of which has not been ascertained. The part itches, becomes 

 red, a weal may result; secondary infection is a common occurrence 

 as a result of scratching them. 



VENOMOUS BEETLES, SNAKES AND LIZARDS. 



These beetles (Coleoptera) and their larvae irritate by means of stiff 

 hairs. Pain, inflammation and sloughing results. In the Solomon 

 Islands there is a venomous snake of unknown species which possesses 

 tubular barbed teeth. These are connected with a poison gland which 

 sometimes causes severe wounds in man. 



There are two lizards celebrated for their poisonous bites, the 

 Trachyderma horribum of Mexico and the Heloderma suspectum of 

 the United States. The former when irritated discharges a white, 

 gelatinous salivary fluid from its mouth which is asserted to produce 

 toxic symptoms. The creature may reach to nearly live feet in length. 



The poison of the latter is passed along grooved teeth. Its effects 

 are similar to an average amount of cobra venom, and should be 

 treated as for that condition. 



POISONS TAKEN ACCIDENTALLY BY MAN. 



Poisoning by fish has been described. 



Sitotoxismus is a term given to vegetable food poisoning. 



Ergotism is not important in the Tropics. 



Lathyrismus is an intoxication caused by the ingestion of Lathvrus 

 satireus and similar species. It exists in India. People who eat 

 vetches in time of famine are liable to be attacked. The disease 

 appears to be due to eating bread composed of flour of the seeds of 

 Lathyrus belonging to the Order LeguminoSce. 



If poverty causes an outbreak it is usuallv endemic. 



If famines cause an outbreak it is usually epidemic. 



Many toxic substances have been separated. 



The incubation is not known. 



The onset is insidious, pain in the back, weakness in the legs and 

 spastic paraplegia manifest themselves. Girdle sensations, dragging 

 feet and wasting of the muscles soon follow. The deep reflexes are 

 increased, ankle clonus is present, muscular electrical reaction dimin- 

 ished, but the reaction of degeneration is absent. Incontinence of 



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