374 Foreign Literature and Science. 



The popular belief in the venomous nature of the toad, 

 Dr. Davy states although of great antiquity, has been rejec- 

 ted as a vulgar prejudice by modem naturlists ; decidedly so 

 by Cuvier ; but like many other long received and preva- 

 lent opinions, it is a true one, and the denial of it by philo- 

 sophers, has resulted from superficial examination. Dr. D. 

 found the venomous matter to be contained in follicles, chiefly 

 in the cutis vera, and about the head and shoulders, but 

 also distributed generally over the body and even on the ex- 

 tremities. On the application of pressure, this fluid exudes, 

 or even spirts out, to a considerable distance, and may be 

 collected in sufficient quantity for examination. It is ex- 

 tremely acrid when applied to the tongue, resembling the 

 aconite in this respect, and it even acts upon the hands. It 

 is soluble, with a small residuum, in water and in alcohol ; and 

 the solutions are not affected by those of acetate of lead, 

 and of corosive sublimate. After solution in ammonia it con- 

 tinues acrid ; it dissolves in nitric acid, to which it imparts a 

 purple color. By combination with potash or soda, it is ren- 

 dered less acrid, apparently by decomposition. As left by 

 evaporation of its aqueous or alcoholic solutions, it is highly 

 inflammable, and the residuary matter that appears to give it 

 consistence seems to be albumen. Though more acrid than 

 the poison of the most venomous serpents, it produces no 

 effect, on being introduced into the circulation ; a chicken 

 inoculated with it was not affected. The author conjec- 

 tures that this " sweltered venom," as it is correctly termed 

 by our great dramatist, being distributed over the integu- 

 ments, serves to defend the toad from the attacks of carniv- 

 orous animals ; "to eat a toad" has long been held as an 

 opprobrious difficulty ; and the animal is still further pro- 

 tected in this respect by the horny nature of its cutis, which 

 contains much phosphate of lime, &c. As the venom con- 

 sists, in part, of an inflammable substance, it is properly ex- 

 crementitious, and an auxiliary to the action of the lungs in 

 decarbonising the blood. This view of its use is confirmed 

 by the fact, that one of the two branches of the pulmonary 

 artery supplies the skin, its ramifications being most nume- 

 rous where the follicles of venom are thickest. Dr. Davy 

 finds the skin of the toad to contain pores of two kinds ; the 

 larger, chiefly confined to particular situations, and which, 

 when the skin is held up to the light, appear as iridescent 

 circles, and the smaller more numerously and generally dis- 



