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PART IV. 
VENOMS IN THE ANIMAL SERIES. 
CHARTER XVI: 
1.—INVERTEBRATES. 
BESIDES reptiles, many other animals possess poison-glands 
and inoculatory organs which they employ, either to defend them- 
selves against their natural enemies, or to capture the living prey 
upon which they feed. 
The venoms that they produce are still, for the most part, but 
little understood. A few of them, however, have excited the 
curlosity of physiologists, especially those secreted by certain 
batrachians, such as the Toad, and certain fishes, such as the 
Weever. Some of them exhibit close affinity to snake-venom, and 
are composed, like the latter, of proteic substances modifiable by 
heat and precipitable by alcohol; others possess altogether special 
characters, and resemble alkaloids. 
The lowest animal group in which these secretions begin to be 
clearly differentiated is that of the Coelenterates. 
A.—COELENTERATES. 
It has been shown by Charles Richet! that the tentacles of sea- 
anemones (Anemone scultata) contain a toxic substance which has 
! Comptes rendus de la Société de Biologie, December 13, 1902; June 6, 
July 25, 1903; February 20, 1904. 
