LEPIDOPTERA IN RELATION TO FLOWERS. 359 



With the Crambi, Tortrices, and Tinese I shall not attempt to 

 deal. I have found species of each division on flower-heads, but 

 the probability is that the great majority pass their lives in the 

 winged state without honey. 



It is an axiom in biology that when an organ remains long 

 unused it becomes atrophied, and this is strikingly exemplified 

 in the table I have given. In the most of the Bombyces 

 the tongue is very much degraded. In Arctia and its allies 

 it is still in evidence, but it is almost quite obsolete in the 

 true Bombyces, as in the typical species, Bomhyx quercusy 

 Linn., and B. rtibi, Linn. The position of the group formerly 

 known as the Cuspidates, tells the same story; in the genus 

 Cilix, for instance, the tongue has quite disappeared. Many 

 of the Geometers are rapidly going the same road, and this is 

 specially evident in those species which have wingless females. In 

 Nyssia zonaria, Schiff, and most of the species of the genus 

 Hybernia, the tongue is either obsolete or rapidly becoming so. 

 Most of the species of the latter genus make their appearance in 

 the winter time, w^ien no flowers are to be found, so that absten- 

 tion must have been forced upon them. Hybernia j^rogemmaria^ 

 Hiib., which appears in the spring, has been recorded as occurring 

 at Sallow blossom. 



On the whole, it may be said that those famihes of the 

 Lepidoptera which are slow of flight, show the least predilection 

 for flowers, whilst the swifter species, which are continually on the 

 wing, are the most frequent visitors to the honey pro\dders. The 

 males of many of the Bombyces are exceedingly swift, but as a 

 rule they remain on the wing only for a short time. The one 

 object in the life of these insects is the reproduction of the species. 

 The Geometers are for the most part slow, and as they are, on the 

 whole, denizens of woods, never wandering far from their place of 

 birth, abstemiousness may have been with them more a matter of 

 necessity than choice. 



Even in the famihes which I have placed on the other side we 

 find great differences. Among the Rhopalocera, or Butterflies, all 

 the species are not alike constant in their attention to flowers. 

 The Pieridse and Vanessidse spend practically the w^hole of their 

 time courting and nectar-imbibing. Nay, the daytime does not 

 seem sufiicient for these indulging insects. Pieris na2n, Linn,, has 



