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M. ETHEL COCHRAN. 



on the tail an abundant poisonous fluid which did not prevent 

 snakes from eating it. Easterly has written of the large granular 

 glands of this salamander which are poisonous, but to what he 

 does not state. 



Baird speaks of the genus Plethodon whose skin exudes a 

 highly glutinous secretion, but he makes no statement of its 

 nature. Gadow says: "Numerous experiments have shown that 

 the poison of toads, salamanders and newts is capable when 

 injected, of killing mammals, birds, reptiles and even fishes, 

 provided of course, the dose be proportionate to the size of the 

 animal. Small birds and lizards succumb as a rule in a few 

 minutes; guinea-pig, rabbits and dogs in less than an hour. 

 This poison of amphibia is not septic, but acts upon the heart 



Raised stone showing pair of red-backs with eggs. (About one half natural size.) 

 (Photographed by Dr. Miller.) 



and central nervous system. Some authorities hold that the 

 poison is an acid, others regard it as an alkaloid." 



The fluid from a red-back's tail is very sticky when placed 

 in the mouth; after a short time, a slight biting sensation is 

 felt for a few moments. 



Several of the salamanders taken from their native haunts 

 had every mark of possessing a regenerating tail. In one case, 

 the tail had been cut or broken off nearly to the hind legs and 

 the bud of a new one had grown out about a quarter of an inch. 



