Some Points in the Evolution of the Lepidopterous 

 Antenna. 



By Dr. T. A. Chapman. Read February (^th, 1899. 



The whole subject of antennal evolution in the Lepidoptera 

 would be much too large for a short paper like this, and so I pro- 

 pose to confine myself to some points only. Really I have only 

 studied some points, and so am not in a position to handle others. 

 Those which I have looked into, chiefly affect the questions con- 

 nected with the relative dispositions of scales and sensory hairs on 

 the antennae, with some others on which the authorities we have on 

 the subject are not in agreement, or appear to have left room for 

 further consideration of some aspects of antennal structure or 

 development. 



I do not know that antennal evolution has been treated in any 

 systematic way before Bodine's "Thesis," published in 1896. 



Bodine deals especially with the different forms and structures 

 of sensory hairs, especially as regards their minute anatomy, their 

 disposition in different families, but covers the other items of 

 antennal structure and evolution in a less complete manner. He 

 leaves some things hardly touched on, and others not very fully 

 treated ; but whatever he does say, and whatever observations he 

 describes, appear to be always well founded and agreeable to the 

 facts whenever I have tested them. 



More recently, Dr. K. Jordan published last summer an account 

 of the antennae of butterflies, in which he gives a great mass of 

 detail as to the structure of butterfly antennae, and in his account 

 of the actual antennae examined he is apparently very correct and 

 accurate. Most of his deductions from his observations are also 

 fully justified ; but some of them seem open to question, and in 

 some statements he makes apart from the Rhopalocera, in which he 

 disagrees with Bodine, there is more doubt as to the validity of 

 his conclusions. 



I am not aware of any other than casual references to antennal 

 evolution outside these two very full and valuable papers. There 

 are such references to isolated items, as Professor Poulton's specu- 

 lations as to the relations of the pupal to the imaginal antennae 

 in Saturnians. 



This was not a point I contemplated fully discussing, as there 

 are no facts available beyond those Professor Poulton was in 

 possession of, and his conclusions and any agreement or disagree- 

 ment with them can be little more than speculation. 



In Saturnians with widely pectinated antennae the males have 



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