SYSTEMATIC INDEX. XXI 



23. Fishing-frog tribe. Have two ventral fins, which some- 

 what resemble feet. The head is large, and compressed 

 downward page 272 



Common Angler, or Frog-fish H>> 



ORDER VI. CHONDROPTERYGIOUS FISH. 



These have cartilaginous gills. 



24. Sturgeon tribe. Have two ventral fins ; and the mouth 

 situated under the head, and without teeth. The body 



is angular, and has several rows of large bony plates .... 273 



Common Sturgeon 273 J Beluga 274 



25. Shark tribe. Have five spiracles, or breathing-apertures, 

 situated at the sides of the neck 275 



White Shark 275 I Angel Shark 276 



Dog-fish 276 I 



26. Ray tribe.' Have five spiracles, or breathing-apertures, 

 situated on the under part of the body, which is broad, 

 thin, and flat 277 



Torpedo, or Electric Ray . 277 I Sting Ray, or Fire-flaire . . 279 

 Skate 278 j 



27. Lamprey tribe. Have the mouth oval, or circular, sur- 

 rounded by a fleshy margin. They have seven spiracles 



on each side of the neck ; and the body is eel-shaped .... 279 



True Lamprey 280 



CLASS V. INSECTS. 



The name of this class of the animated creation is de- 

 rived from a separation in the middle of their bodies, by 

 which they are, as it were, cut into two parts. They have 

 generally six or more legs ; and do not breathe through 

 their mouth, but through pores, or holes, arranged along 

 their sides. Their skin is of a hard or bony consistence. 

 They are furnished with a moveable kind of horns, grow- 

 ing from the head, which are called antennae. 



Insects in general undergo various changes. From the 

 egg is hatched the larva, called also grub, or caterpillar ; 

 this afterwards changes to a pupa, or chrysalis; and, 

 finally, to a perfect insect. 



They are divided into seven orders. 



