ADAPTATIONS 299 



Even the fishes have many modes of self-defense through 

 giving pain or injury to those who would swallow them. 

 The cat-fishes or horned pouts when attacked set immov- 

 ably the sharp spine of the 

 pectoral fin, inflicting a 

 jagged wound. Pelicans 

 who have swallowed a cat- 

 fish have been known to 

 die of the wounds inflicted 

 by the fish's spine. In 

 the group of scorpion- 

 fishes and toad-fishes are 

 certain genera in which 

 these spines are provided 

 with poison glands. These 

 may inflict very severe 

 wounds to other fishes, or 

 even to birds or man. One of this group 

 of poison-fishes is the noki (Emmydridi- 

 thys, Fig. 167). A group of small fresh- 

 water cat-fishes, known as the mad toms 

 (Fig. 168), have also a poison gland attached 

 to the pectoral spine, and its sting is most 

 exasperating, like the sting of a wasp. 

 The sting-rays (Fig. 169) of many species FIG. m A sting-ray 

 have a strong, jagged spine on the tail, "IT""' 

 covered with slime, and armed with broad 

 saw -like teeth. This inflicts a dangerous wound, not 

 through the presence of specific venom, but from the dan- 

 ger of blood poisoning arising from the slime, and the 

 ragged or unclean cut. 



Many fishes are defended by a coat of mail or a coat of 

 sharp thorns. The globe-fishes and porcupine-fishes (Fig. 

 170) are for the most part defended by spines, but their 

 instinct to swallow air gives them an additional safeguard. 

 When one of these fishes is disturbed it rises to the surface, 



