200 



ESSAY ON CLASSIFICATION. 



Part I. 



many new names for groups Avhich had already been correctly limited and well 

 named by his predecessors. He had, no doubt, a desirable object in view in doing 

 this, — he wished to remove some incorrect names ; but he extended his reform 

 too far when he undertook to change those also which did not suit his system. 



CLASSIFICATION OF EHRENBERG. 



The characteristics of the following twenty-eight classes of animals, with a twenty-ninth for Man alone, 

 are given more fully in the Transactions of the Academy of Berlin for 1836, in the paper q. a., p. 138. 



1st Cycle : Nations. Mankind, constituting one distinct class, is characterized by the equable development of 



all systems of organs, in contradistinction of the 

 2d Cycle: Anijials, which are considered as characterized by the prominence of single systems. These are 



divided into : 



A. Myeloneura. 



I. NuTRiENTiA. Warm-blooded Vertebrata, taking 

 care of their young. 

 Cl. 1. Mammalia. 

 Cl. 2. Birds. 



II. Okphanozoa. Cold-blooded Vertebrata, faking 

 no care of their young. 

 Cl. 3. Amphibia. 

 Cl. 4. Pisces. 



B. Ganglioneura. 



A. Sphygmozoa, Cordata. 

 Circulation marked by a heart or pulsating vessels. 



III. Articulata. Re.il articulation, marked by 



rows of ganglia and their ramifications. 

 Cl. 5. Insecta. 

 Cl. 6. Arachnoidea. 

 Cl. 7. Crustacea (including Entomostraca, 



Cirripedia, and LerniBa.) 

 Cl. 8. Annulata. (The genuine Annelids 



exclusive of Nais.) 

 Cl. 9. Somatotoma. (Naidina.) 



IV. Mollusca. No articulation. Ganglia dis- 



persed. 

 Cl. 10. Cephalopoda. 

 Cl. 11. Pteropoda. 

 Cl. 12. Gasteropoda. 

 Cl. 13. Acephala. 

 Cl. 14. Brachiopoda. 

 Cl. 15. Tunicata. ( Ascidife simplices.) 

 Cl. 1G. Aggregata. (Ascidia; composite.) 



VI. 



B. Asphycta, Vascidosa. 

 Vessels without puls.ation. 



TuBULATA. No real articulation. Intestine, a 

 simple sac or tube. 



Cl. 17. B ry o z oa. 



Cl. 18. D i m o r p h a; a . (Ilydroids.) 



Cl. 19. Turbellaria. (Rhabdocuila: De- 

 rostoma, Turbella, Vortex.) 



Cl. 20. Nematoidea. (Entozoa, with sim- 

 ple intestine ; also Gordius and Anguillula.) 



Cl. 21. Rotatoria. 



Cl. 22. Echinoidea. (Echinus, Holothuria, 



Sipunculus.) 

 Racemifera. Intestine divided, or forked, ra- 

 diating, dendritic, or racemose. 



Cl. 23. Asteroidea. 



Cl. 24. Acalephae. 



Cl. 25. Anthozoa. 



Cl. 2G. T r e m a t o d e a . (Entozoa with rami- 

 fied intestine, also Cercaria.) 



Cl. 27. C o m p 1 a n a t a . (Dendrocoela : Pla- 

 naria, etc.) 



Cl. 28. Poly gas trica. 



