38 CLASSES. 



Examples. Tortoise, lizard, snake, frog, sal 

 amander, proteus, siren. 



4. PISCES, oviparous, having fins, and no feet* 

 Heart with one ventricle, blood cold, gills sub- 

 stituted for lungs, covering imbricate scales. 



Examples, Sturgeon, sunfish, pipefish, shad, 

 bullhead. 



ARTICULATED ANIMALS 



ARE DIVIDED INTO FOUR CLASSES. 



5. ANNELIDA, without a bony skeleton and hav- 

 ing red blood Body soft, elongated ; covering di- 

 vided info numerous tron\verse rings. 



Mostly living in water. Some of them secrete 

 calcareous matter, which forms a stony, tubular 

 covering. 



Examples. Earth-worm (angle- worm) sea- 

 pipe, leech, hair-snake. 



6. CRUSTACEA, animals with jointed limbs y 

 'Which are articulated to a hard calcareous crust. 

 They respire by a kind of gills. 



Their gills are pyramidal, made up of plates, or 

 bristly with threads, plumes or simple plates. 

 They generally occupy the base of the feet. They 

 liave mostly four antennae, ten feet and six jaws : 

 one under lip is always wanting. 



Example. Lobsters, crabs, horse-hoofs. 



7. ARACHNID A, animals with jointed limbs, with- 

 out antenna They respire by little openings at or 

 near the termination of the thorax, which lead to 

 organs resembling lungs ; or by little trachea or 

 pipes distributed over the whole body. 



The head and thorax are blended together. 

 They have mostly six or eight eyes, and eight 



