132 



ZOOLOGICAL PHILOSOPHY 



CLASSES 



III. RaDI ASIANS. 



SuboviparoTis animals, free, with regenerating 

 bodies, destitute of head, eyes, or jointed legs ; 

 parts arranged radially. Mouth on inferior 

 surface. 



rV. Worms. 



Suboviparous animals, with soft regenerating 

 bodies ; undergoing no metamorphosis, and 

 never having eyes, jointed legs, nor a radial 

 arrangement of the internal parts. 



2nd Stage. 



No ganglionic 

 longitudinal cord ; 

 .no vessels for cir- 

 culation ; a few in- 

 ternal organs in addi- 

 tion to those of 

 digestion. 



V. Insects. 



Oviparous animals, which undergo meta- 

 morphosis, and have, in the perfect state, eyes 

 in their heads, six jointed legs, and tracheae 

 which spread everywhere ; a single fertiUsation 

 in the course of their life. 



VI. Abachnids. 



Oviparous, having always jointed legs, and 

 eyes in their heads, and undergoing no meta- 

 morphosis. Limited trachae for respiration ; a 

 primitive circulation ; several fertihsations in 

 the course of their life. 



3rd Stage. 



Nerves terminat- 

 ing in a ganglionic 

 ■ longitudinal cord ; 

 respiration by air- 

 carrying tracheae ; 

 circulation absent or 

 imperfect. 



VII. Crustaceans. 



Oviparous, with jointed body and limbs, 

 crustaceous skin, eyes in their head, and usually 

 four antennae ; respiration by giUs ; a ganglionic 

 longitudinal cord. 



VIII. Annelids. 



Oviparous, with elongated and ringed bodies ; 

 no jointed legs, rarely any eyes ; respiration by 

 gills ; a ganglionic longitudinal cord. 



IX. ClBRHIPEDES. 



Oviparous, with a mantle and jointed arms, 

 the skin of which is homy ; no eyes ; respira- 

 tion by giUs ; ganglionic longitudinal cord. 



X. Molluscs. 



Oviparous, with soft moist bodies, vmjointed, 

 and with a variable mantle ; respiration by 

 gUls of various shapes and situations ; no spinal 

 cord, nor ganghonic longitudinal cord, but nerves 

 terminating in a brain. 



ith Stage. 



Nerves terminat- 

 ing in a brain or a 

 i ganglionic longitud- 

 inal cord ; respira- 

 tion by giUs ; arteries 

 and veins for circu- 

 lation. 



