brown, is very conspicuous in the cabinet; but when it is 

 at rest at the bottom of a " tussock," these markings har- 

 monise most perfectly with the lights and shadows of the 

 yellowish grass-stems, and in this enviroftment the insect 

 presents as complete and beautiful an example of protective 

 resemblance as our own " Orange-tip " on its favourite white 

 Umbelliferous flowers. Percnodaimon [Erehia) pluto Fereday 

 is in appearance and structure, as well as in habits, wonder- 

 fully like some of the black Erebias of the European Alps, 

 and is fairly widely distributed and sometimes common on 

 shingly mountain slopes at elevations between 4000 and 6000 

 feet. As I have unfortunately no practical experience of this 

 mountain butterfly, I cannot refrain from quoting the very 

 interesting remarks of Mr. H. Hamilton on the habits of the 

 insect as observed by him in its native surroundings.* " Erehia 

 pluto can only be located when the sun is shining strongly 

 and continuously. This beautiful black butterfly is then to 

 be seen hovering over the shingle-slips, and apparently follow- 

 ing well-defined air-tracks. It was noticed that the best way 

 to capture them was to sit close to a place they had been 

 seen to pass, and keep perfectly still. Presently one would 

 come sailing along, and apparently not notice the collector. 

 A very quick movement with the net was necessary to catch 

 the insect, and if you missed the first stroke the chances 

 were all on the butterfly escaping. On being disturbed they 

 make rapid jerky upward movements, and soon get out of 

 the danger-zone, flying away to some other slope. As soon 

 •as the sun is obscured by a cloud all the butterflies alight 

 and remain motionless until the sun shines again. As sun- 

 shine is the exception rather than the rule on these mountain- 

 tops, Erehia-hunting is very trying to the patience." 



Erebiola hutleri Fereday is also restricted to similar high 

 altitudes, but is a much more local and less common insect 

 than P. pluto. To quote Mr. H. Hamilton again : f " As a 

 rule, the habits of the E. hutleri are sluggish, and it does not 

 make long flights ; it frequents some particular tussock-clump 

 and flutters about there. The position of the female is 

 generally indicated by watching the movements of the males, 

 * Trans. N.Z. Inst., XLIII, p. 117. f L.c, p. 122. 



