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restricted ; five may be regarded as common insects ; and all 

 are liable to aberration in a greater or less degree, but in one 

 only do we find great local variation. 



I am not aware of any sufficient reason for following a 

 particular sequence, and therefore will commence with 



Triphcena fimbria, L. This is the largest and most hand- 

 some species in the genus. It affords a striking example of 

 colour variation, the extremes being a pale wainscot-brown 

 and a dark olivaceous-brown, while intermediates occur of 

 varying shades between the two. It is also liable to a certain 

 amount of variation in the markings of the primaries, the 

 outer line of the central band being acutely angled in some 

 specimens, while in others it is rounded, and the dark spot 

 near the apex is sometimes strongly produced, but occasion- 

 ally almost wanting. There does not appear to be any 

 relation between the variation in colour markings, nor has 

 locality any great effect upon either ; thus we find the light 

 and dark forms among both southern and northern specimens. 

 It has been met with throughout the greater part of the 

 British Islands, as far north as Elgin, from which locality are 

 two of the specimens exhibited, these favour the intermediate 

 rather than the extreme forms ; as do also two from North 

 Wales. Its Continental range extends from Asia Minor and 

 the southern countries of Europe to South Scandinavia. 



Triphmia proniiba, L., is generally regarded as the 

 commonest species of the group, and is of general distribution 

 throughout the whole of the British Islands ; indeed, it has 

 the largest geographical range of any species of the genus, 

 extendmg over almost the whole of the European district 

 except the Polar regions. It is liable to very great variation, 

 but locality appears to have no effect upon it in this respect. 

 We find the handsomely mottled type sitting on the sugared 

 trees in our Kentish woods, side by side with the plain 

 unicolorous innuba forms, and in the north of Scotland a 

 similar range of variation exists. The exhibit comprises 

 series from Kent and Forres, two specimens from North 

 Wales, and sundry German types for comparison, these 

 represent but a few of the forms that occur in any one of 

 the localities, but it will be seen how closely the various 

 forms from the one and the other match each other. 



Triphcena ianthina, Esp., is one of the most constant species 

 of the group, the chief variation being a slight difference in 

 the depth of coloration, this is most marked in some of the 

 Scotch specimens, which are somewhat lighter and redder 

 than those from the more southern districts ; but even here 



