AS BOTANISTS 55 



larger number of butterflies than have been recog- 

 nized by our senses as odorous, it would seem a 

 warrantable conclusion that, although we cannot 

 perceive their odor, they nevertheless produce 

 odors recognizable by their mates. Now we know 

 in a similar way that many plants are odorous 

 quite apart from their flowers ; and if one, with 

 this idea in mind, will but watch the movements of 

 a mother butterfly seeking a spot whereon to lay 

 her eggs, he will not fail to recognize that many of 

 these actions seem particularly in keeping with the 

 notion that she is at work scenting the various 

 plants that bear a general resemblance in their 

 aspect to the one which she seeks; many, indeed, 

 which have no such general appearance, settling or 

 half settling in a dozen different places in the near 

 vicinity of the plant, reaching it by nearer and 

 nearer approaches, and finally settling with satis- 

 faction at the desired S]3ot. To such an observer 

 it will seem tolerably clear that it is to the sense 

 of smell that butterflies owe their recognition of 

 botanical species. 



