122 



ESSAY ON CLASSIFICATION. 



in ascertaining the minor modifications characteristic of tlie 

 different families. It may even be, that further investi- 

 gations will greatly modify the general classification of 

 the whole branch. The class of Fishes 1 may require sub- 



1 FORCHHAMMER, (G.,) De Bleniiii 

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 4to. fig. Ueber das Ei einiger Lacbs- 

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 BAER, (K. E. v.,) Untersuchungen 

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 DAVY, (J.,) On tbe Development of 

 the Torpedo, Philos. Trans. R. Soc., 

 1834. Some observations on the ova 

 of the Salmon, in relation to the dis- 

 tribution of species, Trans. Roy. Soc. ; 

 London, 1856, I, p. 21. FILIPPI, 

 (FiL. DE,) Memoria sullo sviluppo del 

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 chiv, 1840, p. 185. Lettre sur les 

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 sons eprouvent avant qu'ils aient pris 

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 Sur le developpement embryonaire 

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 WYMAN, (J.,) Observations on the 

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 fig. On some peculiar modes of ges- 

 tation observed in certain animals of 

 Guiana, Proc. Bost. Nat. Hist., 1857. 

 AGASSIZ, (L.,) Extraordinary Fishes 

 from California, constituting a new 



