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THE YOUNG NATURALIST. 



second brood is occasion ally wanting. In Scotland, I believe, there is never 

 more than one, and the form Artaxerxes is always produced, though the white 

 spot varies much in size. Here (in Durham) we get all the forms, but it is 

 only in the first brood that Artaxerxes is produced. It would appear there- 

 fore that only the larvae that pass the winter can produce this form. We 

 have imagined we got it with larger white spots when we had a severe winter, 

 but I cannot say we made notes that would enable me to state this as a fact. 

 Besides the ordinary varieties other forms occasionally occur. It is not un- 

 frequent with a black disc spot in a white ring, and when the white spot is 

 large in the fore-wings, there is often a trace of a white circle to the discoidal 

 spot on the hind-wings. The late John Sang took one here with a distinct 

 white spot on the posterior as well as the anterior wings. The orange lunules 

 are sometimes large and distinct, sometimes wanting, with every possible inter- 

 mediate form. On the underside the spots vary greatly. I have one without 

 any but the discoidal spot. They also occasionally run into streaks, as they do 

 in others of the genus. I have taken one of the variety (estiva, which has 

 the underside browner than usual. 



Agestis, so far as I have seen, flies about the sides of banks rather than on 

 level ground, and though the food-plant grows on dry places on the bank 

 sides, the butterfly dearly loves a bit of damp or swampy ground. Wherever 

 a little streamlet trickles down the hill, grown up with rushes and long grass, 

 there we will find Agestis sporting in the sun or settling on the rush stems. 

 It is a pugnacious little fellow, and will brook no intruder in its own domain, 

 driving off not only such species as Alexis and Pamphilus, but even larger 

 species should they come near. When so engaged, it attacks fiercely, and 

 then returns to its resting place. This Vanessa-like, habit does not obtain at 

 other times. It is on the wing as soon as the dew is off the grass, and con- 

 tinues to fly till between four and five in the afternoon, after which it may be 

 picked off the stems, and is easily distinguished from others of the genus by 

 the underside of the wings being much browner. 



The larva feeds on the underside of the leaves, and may be found by tap- 

 ping the plant gently, and then searching for it on the surface of the soil. 

 We get at the same time and place the beautiful larva of Procris geryon, 

 which feeds on the same plant. 



It is no wonder that this insect has had a variety of names. Beside the 

 named forms, the type has been called Alexis, Agestis, Medon, Astrarche, and 

 Idas. Which of these has precedence is yet an undecided point. At present 

 it would seem that Scopoli's name Alexis given in 1763, has the prior 

 claim. Staudinger calls it Astrarche, Bergstrasser, 1779 ; Newman prefers 

 Medon, Esper, 1777 ; Stainton uses Agestis, W.V., 1776, which was also 



