43 
were seen was 25th of same month. Not one was seen subsequently 
in this year. Between these dates it was fairly abundant, and this 
was a year for a species to linger rather than be hurried in its courses. 
From two to three weeks usually averaged each brood’s days. And 
only by collecting in a series of localities (seven) could one calculate 
on working bellargus in second brood for five weeks round Brighton. 
In the earliest locality it would be over (or more than over) before its 
appearance in the last. This refers to years prior to 1899, and to 
S. Downs. But in 1903, 1904, 1905, 1906, a new experience has been 
one’s lot. 
The dates for these four consecutive years (to which 1907 is added 
since reading of paper) are— 
First-Brood. Second-Brood. 
*1903 
1904 
1905 
1906 
1907 
36 days 
29 ,, 
63 „ 
40 „ 
49 „ 
47 days 
37 
47 
47 
51 
? > 
> 1 
5 » 
> » 
The days on which bellargus was on the wing in these years 
covered over 22 per cent., 18 per cent., 30 per cent., 24 per cent., 
27 per cent, of these years respectively. 
Leaving the periods of emergence, etc., and diverging to variation 
in special years—and taking in corydon as well—the observation of 
1887 and 1888, when I visited regularly two localities, I was firmly 
convinced that these two years showed as regards themselves as 
follows :— 
1887: very hot, sunny, dry summer; exaggeration of sexual 
dimorphism, $ s brilliant, ? s no blue. 
1888 : Late, wet, mostly wretched summer; most of 5 s with 
blue taken this summer, and all the darkest $ s taken previously to 
1904 were of this year’s capture. The comparison of long series of 
these two years especially of corydon , taken in an endeavour to get all 
possible variation, was most striking in the manner above indicated. 
Possibly a further remark or two on other variation in imago of 
corydon will not be quite useless, especially considering that, as 
regards the differentiation of 5 of bellargus from corydon, there is, I 
believe, no written description which precludes the possibility of error 
in identification, however easily familiarity may enable one to readily 
distinguish every individual. 
In my former collection I had a corydon taken in last week of July, 
1888. This verbally (so to say) was indistinguishable from bellargus as 
to colour, shape, fringes, markings of upper- and under sides, with all 
the admirable neatness and cleanly marked detail of the latter, except 
for one character not, to my knowledge, anywhere described as a 
mark of identification, a propos of which character a series is shown. 
Not that it never fails, does one suggest; but so often markedly 
present in corydon, it is, I think, final when well-marked. 
On the margins of the wings, on the undersides, where the dark 
line cuts off the fringes from the wing, and where the nervures end 
In this table one and the same single locality all through. 
