INTRODUCTION. ^5 



of this procedure must arise from the reflection, that 

 an ill-estabhshed species cannot stand, that sooner or 

 later the error must be discovered, and that a false 

 judgment in this respect will be held to betray inac- 

 curacj, or insufficient powers of discrimination. He 

 should furthermore be encoui'aged to keep back his 

 discoveries until he is fully satisfied of their accuracy, 

 by the assurance that, in the final opinion which is to 

 fix his reputation, a single species well estabhshed, 

 with its place and relations ascertained, will redound 

 more to his honor than a thousand erroneous ones. 

 These remarks are intended only for the ingenuous 

 and well-meaning naturalist, but it is greatly to be 

 feared that there have been others ayIio, for the sake of 

 a little temporary reputation, have thrust themselves 

 without qualification among the laborers of Natural 

 History, and have deluded themselves with the idea, 

 that because they could write nobis after false species, 

 others would be blmd to their demerits. The career 

 of such persons must always be short ; they are the 

 false coin of science, and will sooner or later be 

 stamped as uncurrent. The other of the causes alluded 

 to is, the hypothesis, held by some persons, that the ani- 

 mals of the respective continents, however near their 

 affinities may be, are in every case specifically distinct 

 from each other ; and hence, as there are animals of cer- 

 tain famiUes on both continents which cannot be dis- 

 tinguished from each other by any well-marked char- 

 acters, it has resulted, that species possessing apparent 



