POISONOUS PLANTS AND ANIMALS in 



fishes and sea-urchins have a very deadly poison 

 associated with them, which has recently been examined. 

 Among insects we have the bees, wasps, and ants, with 

 their terminal stings ; caterpillars, with poisonous hairs ; 

 gnats, with poisonous mouth glands. Residents in 

 mosquito-infested countries become " immune " to the 

 poison of gnat-bite, but not to the deadly germs of 

 malaria and yellow fever carried by the gnats. The 

 centipedes have powerful jaws, provided with poison- 

 sacs ; the spiders have stabbing claws, fitted with poison- 

 glands. Shell-fish, such as crabs and lobsters, do not 

 possess stings or poison-sacs, but some of the whelk-like 

 sea-snails have poison-glands, which secrete a fluid deadly 

 to other shell-fish. We have already spoken of the poison- 

 spines of fishes ; among reptiles it is only some of the 

 snakes which are poisonous, and are known to have poison- 

 glands connected with grooved fangs. Only one kind of 

 lizard the Heloderm of North America, already men- 

 tioned has poison-glands in its mouth, but it has no 

 special poison-fangs, only small teeth. There is a most 

 persistent and curious popular error to the effect that the 

 rapidly moving bifid tongue of snakes and lizards is a 

 "sting." It is really quite innocuous. No sting is 

 known among birds, although some have fighting 

 " spurs " on the leg, and " claws " on the wing. 



Only the lowest of the mammals or warm-blooded 

 hairy quadrupeds namely, the Australian duck-mole 

 (Ornithorhynchus) and the spiny ant-eater (Echidna) 

 have poison-glands and related " spurs, " or stings. They 

 have on the hind-leg a " spur " of great size and strength, 

 which is perforated and connected with a gland which 

 produces a poisonous milky fluid. Recent observations, 

 however, as to the poisonous character of this fluid are 

 wanting. Many mammals have large sac-like glands, 

 which open by definite apertures, in some cases between 



