Chap. II. FAMILIES. 157 



cannot be considered as a character of branches, nor of classes; let us now 

 examine, further, whether it is a character of species. A rapid review of some of 

 the best known t^'pes of the animal kingdom, embracing well-defined genera with 

 many species, will at once show that this cannot be the case, for such species do 

 not generally show the least difference in their forms. Neither the many species 

 of Squirrels, nor the true Mice, nor the Weasels, nor the Bears, nor the Eagles, 

 nor the Falcons, nor the Sparrows, nor the Warblers, nor the genuine Woodpeckers, 

 nor the true Lizards, nor the Frogs, nor the Toads, nor the Skates, nor the Sharks 

 proper, nor the Turbots, nor the Soles, nor the Eels, nor the Mackerels, nor the 

 Sculpins, nor the genuine Shrimps, nor the Crawfishes, nor the Hawkmoths, nor 

 tlie Geometers, nor the Dorbugs, nor the Spring-Beetles, nor the Tapeworms, 

 nor the Cuttlefishes, nor the Slugs, nor the true Asterias, nor the Sea-Anemones, 

 could be distinguished among themselves, one from the other, by their form only. 

 There may be differences in the proportions of some of their parts, but the pattern 

 of every species belonging to well-defined natural genera is so completely identi- 

 cal that it will never afford specific characters. There are genera in our system 

 which, as they now stand, might be alluded to as examples contrary to this state- 

 ment ; but such genera are still based upon very questionable features, and are 

 likely to be found in the end to consist of unnatural associations of heterogeneous 

 species : at all events, all recent improvements in Zoology have gone to limit 

 genera gradually more and more in such a manner, that the species belonging to 

 each have shown successively less and less difference in form, until they have 

 assumed, in that respect, the most homogeneous appearance. Are natural genera 

 any more to be distinguished by their form one from the other? Is there any 

 appi-eciable difference in the general form, — I say purposely general form, because 

 a more or less prominent nose, larger or smaller ears, longer or shorter claws, 

 etc., do not essentially modify the form, — is there any real diflerence in the general 

 form between the genera of the most natural families? Do, for instance, the 

 genera of Ursina, the Bears, the Badger, the Wolverines, the Raccoons, differ in form ? 

 Do the Phocoidas, the Delphinoidre, the Falconin*, the Turdiniv, the FringillinsB, 

 the Picinte, the Scolopacinoe, the Chelonioidae, the Geckonina, the Colubrina, the 

 SparoidjB, the Elaterida^, the Pyralidoidoe, the Echinoidoe, etc., differ any more among 

 themselves ? Certainly not ; though to .some extent, there are differences in the 

 form of the representatives of one genus when compared to those of another genus; 

 but when rightly considered, these differences appear only as modifications of the 

 same type of forms. Just as there are more or less elongated ellipses, so do we 

 find the figure of the Badgers somewhat more contracted than that of either the 

 Bears, or the Raccoons, or the Wolverines, that of the Wolverines somewhat more 

 elongated th;m that of the Raccoons; but the form is here as completely typical 



