THE ANIMAL KINGDOM. 31 



III. AMPHIBIA. 



The heart has one auricle and one ventricle ; their blood is cold and red. 



The lungs refpire according to the will of the animal. 



The jaws are horizontally incumbent on each other. 



The penis, in many fpecies, is double ; the eggs of moft are membranous. 



Their organs of fenfe are, the tongue, noftrils, eyes, and ears. 



They are covered with a naked {kin. 



Their motive organs are various in different animals, and wanting in fome. 



IV. FISHES. 



The heart has one auricle and one ventricle ; the blood is cold and red. 



They have compreffed external gills inftead of lungs. 



The jaws are horizontally incumbent on each other. 



The penis is wanting in mod. The eggs have no white. 



Their organs of fenfe are, the tongue, noftrils ? eyes, and ears. 



They are covered with imbricated fcales. 



Their motive organs are fins fitted for fwimming. 



V. INSECTS. 



The heart has one auricle and one ventricle, propelling, cold, colourlefs, fanies. 



They breathe by pores on the fides of their bodies. 



Their jaws open laterally. 



They copulate by means of an intrant penis. 



Their organs of fenfe are, the tongue, eyes, antennae on the head, which is defti- 



tute of brain, and neither ears nor noftrils. 

 They are covered by a boney coat of mail. 

 Their motive organs are legs in all, and wings in a great many. 



VI. WORMS. 



The heart, for the moft part, has one ventricle without any auricle, and propels a 



cold colourlefs fanies. 

 Their breathing pores are obfcure and uncertain. 

 Their copulation and penis are various ; fome are hermaphrodites, having both 



male and female parts in one individual. 

 Their organs of fenfe are tentacula in all, and eyes in moft ; the brain, ears, and 



noftrils, are wanting. 

 They are covered with calcareous fhells, or have no covering except fpines. 

 They have neither feet nor fins.. Thus 



