Zygena Trifolit. 431 
On the 13th of June this same year (1866), I went to 
the marshy place in Tilgate Forest, before mentioned, in 
search for larvee, hoping, of course, to find them identical 
in their markings with the Stowe Wood caterpillar. I 
found some Zygena larve there in tolerable abundance, 
feeding on the same plants as in Stowe Wood Marsh ; 
their markings, to the minutest particular, were identical 
with the Stowe Wood caterpillars, the same shght range 
of variation, and no more. These larve afterwards, in the 
first week in July, produced the late T'rifolii I had found 
there in 1864, and at the same time the Stowe Marsh 
caterpillars began to come out, and produced the late 
Trifolii, exactly identical with those of Tilgate Forest. 
Here, then, were two colonies, one in Northamptonshire, 
one in Sussex, traced from larva to imago, and exactly 
agreeing in every point, including time of appearance. 
On the 8rd of July, while these insects from Tilgate and 
Stowe Wood were just beginning to come out, I visited 
Barnwell Wold, a locality intermediate in geographical 
position, and, as I expected, the early Trifolii was over ; 
I caught five only, very worn; I was told it had been 
abundant. 
I had been also informed of another locality near 
Oxford, where T'rifolii occurred, viz., the dry slopes of 
Shotover Hill; in 1867, M. Dembski sent me two Zygena 
larvee found there: these larve had all the characteristics 
of the Barnwell Wold caterpillar, to wit, the tendency 
to the confluency of the dorsal spots, and the tendency 
to the x -like shape, which I have never seen in the late 
Trifolii; to breed one of these was the only link I now 
wanted, and at a consultation held with Professor West- 
wood, it was determined to put one into whiskey and 
water, and breed the other; the weakest looking was 
accordingly consigned to the bottle, and two days after- 
wards the other on which I rested my hopes, produced 
an abundant crop of Ichneumons. 
In 1870, on June 17th, the late Trifolii was not out im 
Tilgate Forest ; on June 18th, I found the early Trifolii at 
Folkestone over, I caught a few worn specimens only. 
I had written a few days previously to Mr. Hellins, asking 
him the nature of the locality of the caterpillars described 
by him in ‘Ent. Mo. Mag. iii. p. 118,’ and also sending 
him some larve, of the late Tvrifolii, from Stowe Wood, 
Mr. Hellins kindly answered my letter at once, and said, 
