i 1867.] 251 
I 
Occv/rrence of Eros affinis, a species new to Britam. — Mr. J. Hardy, of Emden 
Street, Hulme, Manchester, has sent to me for examination a fresh and perfect 
carded specimen of an insect which he considered to be specifically distinct from 
E. Aurora, and which I have determined to be E. aflnis, Payk. ; Kies., Ins. Deutsch., 
IV., 441, 4. It was taken last year at Killarney by Mr. Hardy's son, who also at the 
same time found a pair of elytra of the same species floating in the Lake. The insect 
occurs in Sweden, and elsewhere within our range. It is rather smaller than E. 
Aurora, and readily distinguishable from that species by its black thorax, of which 
the anterior margin only is obscurely reddish. Compared with E. Aurora, moreover, 
it exhibits the following diagnostic characters ; — its antennae are shorter and 
thicker, having the 3rd joint small and little longer than the 2nd ; its thorax is 
somewhat broader, less contracted in front, with the discal depression difierently 
shaped, and the anterior margin minutely but sharply emarginate in the middle ; 
and its elytra are shorter, with the interstices between the four elevated ridges on 
each not broken up by supplementary longitudinal striae, so that they are uninter- 
ruptedly transversely reticulate. — Id. 
Note on a clarTc variety of Cicindela cativpestris. — My son, Dr. A. Chapman, of 
Abergavenny, captured a black variety of C. campestris in the fii'st week of October, 
1858, on the hill bounding Glen Finnart on the South, on the west side of Loch 
Long. — T. Chapman, 56, Buchanan Street, Glasgow. 
[This specimen, thanks to Mr. Chapman's spontaneous generosity, now adorns 
my cabinet. It is in perfect condition, and exhibits the outline of its cream- 
coloured spots with great sharpness, owing to its dark ground-colour. The 
ordinary outer central spot on each elytra is absent. It is, of course, the var. 
funehris figured by Sturm. — E. C. R.] 
Notes on variation in Lepidoptera. — There seems much unanimity of opinion 
amongst Entomologists upon two points connected with the variation of Lepidoptera, 
The first of these is, that there is a true physiological cause for them ; and the 
second, that this cause is not too deeply hidden for our minds to find it out. 
There are three general causes admitted by all, and on which no dispiate can 
arise. These are — Climate, Isolation, and Hereditary Descent. The first on this 
list — Climate, is cleai'ly " a ratio compounded of ratios," and may involve many 
causes in one ; the second may depend on the first, or last, or on both together ; 
and the third cannot, of course, originate a variety, but only perpetuate it. It ia 
clear, therefore, that we must look deeper than these. 
The more specific causes which deserve investigation are as foUow : — 
1. Heat. — It is difficult to give any physiological reason why heat alone should be 
the cause of variation. The experiment of rearing our common Lepidoptera in 
an orchis house for several generations could, however, easily be tried. 
2. Light. — This cause has strong analogies in its favour ; any but negative experi- 
ments with it are, however, very difficult to devise. 
3. Food. — "We have bearing upon this point the successful case of Cleora lichen- 
aria, quoted by the Rev. J. Greene. We have also the fact that larvae are 
coloured frequently by their food. Physiologically, analogy gives us the 
