VENOMS IX THE ANIMAL SEEIES 



293 



in rocks, and fishermen are afraid of being stung by them 

 (fig. 102). 



Their poison-apparatus resembles that of the Weevers, but is 

 less developed. It is situated in the culs-de-sac formed by the 

 opercular spines. The culs-de-sac are lined with cells which pro- 

 duce a toxic secretion only during the spawning season, from 

 November to the end of January. This fact explains how it is that 

 the species of Cottus are declared by certain fishermen to be very 

 venomous, while others say that they are absolutely harmless. 



The genera Scorpcena, Pterois and Pelor also belong to the 

 same group. 



Fig. 103. — Sccri'pcsna grandicornis (Caribbean Sea). (After Savtschenko.) 



In ScorpcBua the body is clothed with scales, and the head is 

 large, slightly compressed, armed with spines, and has a bare pit 

 behind ; the single dorsal fin is provided with eleven spiny rays, 

 and there are seven branchiostegal rays. ScorjJCByia grandicornis 

 (fig. 103), found in the Caribbean Sea, is from 30 to 50 cm. in 

 length, and has the back red and the eyes and belly yellow ; 

 Scorpcena diaholus (fig. 104), which occurs in the Indian Ocean 



