IX THE HISTORY AND SCOPE OF ZOOLOGY 323 



(e) Ore antico ; corpore pedato : Apkrodita, 



Nereis. 



(/) Ore infero central! : Medusa, Asteria, 

 JSchinus. 



Order 3. Testacea. 



Genera : (a) Multivalvia : Chiton, Lepas, Pholas. 



(b) Bivalvia ( = Conchce) : My a, Solen, Tellina, 



Cardium, Mactra, Donax, Venus, Spon- 

 dylus, Chama, Area, Ostrea, Anomia, 

 Mytilus, Pinna. 



(c) Univalvia spira regular! ( = Cochleae) : Argo- 



nauta, Nautilus, Conus, Cyprcea, Bulla, 

 Valuta, Buccinum, Strombus, Murex, Tro- 

 chus, Turbo, Helix, Nerita, Haliotis. 



(d) Univalvia absque spira regulari : Patella, 



Dentalium, Serpula, Teredo, Sabella. 

 4. Lithophyta. 



Genera : Tubipora, Madrepora, Millepora, Celle- 



pora. 

 5. Zoophyta. 



Genera : (a) Fixata : Isis, Gorgonia, Alcyonium, 

 Spongia, Flustra, Tubularia, Corallina, 

 Sertularia, Vorticella. 



(b) Locomotiva : Hydra, Pennatula, Tcenia, 

 Volvox, Furia, Chaos. 



The characters of the six classes are thus given by 

 Linnaeus : 



Cor biloculare, biauritum ; ) viviparis, Mammalibus; 



Sanguine calido, rubro : j oviparis, Avibus. 

 Cor uniloculare, uniauritum; 1 ) pulmone arbitrario, Amphibiis ; 



Sanguine frigido, rubro : j branchiis externis, Piscibus. 

 Cor uniloculare, inauritum ; ) antennatis, Insectis ; 



Sanie frigida, albida : j tentaculatis, Vermibus. 



1 The anatomical error in reference to -the auricles of Reptiles and 

 Batrachians on the part of Linnaeus is extremely interesting, since it 

 shows to what an extent the most patent facts may escape the observa- 

 tion- of even the greatest observers, and what an amount of repeated 

 dissection and unprejudiced attention has been necessary before the 

 structure of the commonest animals has become known. 



