PLEBEIUS ARGUS. 227 



position, and also in number, but there is, in all specimens examined, 

 at least one at each situation noted. The antennae are 7mm. long, 

 and about 03mm. wide, with a wider square portion (scape) at vertex. 

 All these appendages are sculptured in the usual fine network of 

 raised lines, but very irregularly. The wings have the network in 

 larger meshes and finer lines. In the empty case, the veins are very 

 evident on the wing-cases, but, in mounted specimens, these are not 

 seen. The hind-margin of the wing is marked by lines due to 

 infringing on the 4th and 5th abdominal segments, and a small 

 border, perhaps, sinks into the incision, but nothing distinctly like 

 " Poulton's line " is seen. I observe I have not noted the acicular skin- 

 points of the ventral aspect of the 5th and 6th abdominal segments. 

 It is very interesting to follow the variations from point to point of 

 the skin-rosettes, and the meshes of net-work, but it would be even 

 more tedious than I am alread} 7 , to attempt to describe them 

 (Chapman). 



Time of appearance. — In Britain the species is entirely single- 

 brooded. Going over the winter as egg, the young larva may emerge 

 any time between the end of February and commencement of May, 

 and, according to its position being suitable or unsuitable, may feed up 

 comparatively quickly or slowly ; hence, though the species is rarely 

 on the wing until the last ten days of June, emergences may continue 

 until well into August. There is considerable difference in the time 

 of appearance in early and late seasons, as our detailed list of captures 

 and emergences show T . But the species is not so completely single- 

 brooded on the continent ; it is, we have no doubt, partially double- 

 brooded in Fontainebleau Forest, where we found the species fully out 

 on June 28th, 1907, and also found a few examples in good 

 condition quite late in August, 1899 ; similarly, at Gresy-sur-Aix, a 

 partial second-brood appears to occur in mid-August, a few fine 

 examples then occurring where the species is not uncommon in June, 

 which we do not think are merely a continuous single-brood as is the 

 case in Britain. Quite in the south of France, Powell says {in litt.) 

 that there is reason to believe the species to be double-brooded, 

 perhaps partially triple-brooded, in lowlying parts of the Mediterranean 

 littoral. He has not tried to breed second- brood examples from the 

 egg, but the fact that P. aryus is abundant and getting well-worn 

 near the Hyeres' marshes at the end of May, and that it is abundant 

 and fresh in the same locality during the second and third weeks in 

 August, is pretty convincing evidence of a second (perhaps third) 

 brood, as he says he has never looked here for aryus in June or July. 

 Oberthur, however, states (Etudes, xx., p. 26) that, near Rennes, it is 

 only single-brooded, occurring at the end of June and beginning of 

 July. It is also noted as occurring in Allier, in May and July 

 (Peyerimhoff); from June 15th- August 30th, in Indre (Sand); in 

 June, on the coast, in Eure (Dupont); common almost everywhere in 

 June and July, up to 6000ft., in the French Pyrenees (Elwes); in June 

 and August in Loir-et-Cher (Chevillon). The evidence available 

 indicates that the species is largely single-brooded in Germany, 

 although some authors suggest a second-brood, e.g., May, and again 

 in July-August, in Eutin (Boie); May and early June, and again end 

 of July-August, in Hanover (Peets), but Glitz gives June to August 

 for the same district ; in May and August, in Hesse (Glaser), although 



