THE ENTOMOLOGIST 



Vol. XXX.] APEIL. 1897. [No. 407. 



ON THE SUBORDINATE INFLUENCE OF CLIMATAL 

 CONDITIONS IN DECIDING THE MORPHOLOGICAL 

 CHARACTERS, WITH SPECIAL REFERENCE TO THE 

 RHOPALOCERA. 



By W. Harcourt-Bath, 



The preponderating influence of the organic environment in 

 determining the distinctive or morphological characters of the 

 Rhopalocera is probably much less apparent than real. It is, 

 however, a more difficult task to prove than its influence with 

 respect to their geographical and vertical distribution. Never- 

 theless, I am perfectly convinced myself that the climatal con- 

 ditions similarly play only a subordinate part in the matter, and 

 what effects derive their origin from the physical environment 

 do not possess the determining factor, and only operate upon the 

 organism indirectly. 



I will endeavour to support this hypothesis by certain facts 

 and conclusions which I have obtained during the course of my 

 investigations respecting the various problems connected with 

 their vertical distribution. 



I will first of all add a few words to the article by my pen 

 which appeared in the December (1896) issue of the ' Entomo- 

 logist ' with reference to the latter subject. The conception I 

 have formed of the phenomenon presented by the various zones 

 of vegetation, with their accompanying fauna, stretching from 

 the equator upon either side to the two poles, and likewise from 

 the bases of the various mountain chains to the line of congela- 

 tion, is that it represents a somewhat parallel or analogous case 

 to the phylogenetic and ontogenetic stages in the progress 

 respectively of genera and species. This is, of course, not 

 strictly the case, but it represents in a very fair degree the 



ENTOM. APRIL, 1897. I 



