63 
dorsal piliferous tubercles are arranged, as Comstock noted, in two 
pairs, those of the anterior pair being closer together than those of the 
posterior pair, 
Comstock has already described the pupa in detail. Essentially, 
it is 5 mm. long, brown, with the wing-cases and the dorsum of the 
thorax darker than the rest. There are two transverse rows of teeth 
on the dorsum of all the evident abdominal segments except the last, 
and the blunt anal segment bears posteriorly six stout blackish ex- 
curved hooks, and several delicate hooked filaments. 
The oval white silken cocoon, 10 mm. long, is usually inconspicu- 
ous on account of the particles of excrement or bits of floral tissue 
attached to it. 
The adult ( Plate II., Fig. 11 ). expanding only 8 to 10 mm., is a silky 
dark brown moth, with brilliant silvery markings that are quite char- 
acteristic. The most conspicuous marks are those that make the two 
parallel crescents when the wings are closed. Along the anterior bor- 
der of the front wing are eight silvery marks (sometimes nine) in 
form and position as shown in the figure. In fresh specimens the 
front wings show a few patches of iridescent scales. The hind wings 
are dark brown, with pale fringes. 
Life History. — Our field and insectary observations show that 
there are three generations of this species every year, without much 
overlapping of the broods. Here, the moths of the first generation be- 
gin to emerge from the pupae May 15, attain their maximum numbers 
May 24 (along with the clover seed-midge), and disappear during the 
last of June. In 1907 — a late season — we saw no moths until May 21, 
and they were most numerous May 30. The moths of the second gen- 
eration appear in the form of a few scattering individuals as early as 
June 25, but most of them are on the wing during the third week of 
July, and a few battered specimens linger over into the first week of 
August. The moths of the third generation appear as early as Au- 
gust 19, become abundant by August 30, continue to emerge as late as 
September 12, and die oflf by the last of September. Some margin — 
a few days — should, of course, be allowed for these dates, which are 
here given as they appear on our note-slips. 
Eggs laid September 2 hatched September 7. The larval period 
is from one month to five weeks. The pupal period in July is between 
two and three weeks. It is possible to find larvae of various sizes at 
any time from the last week of May until winter sets in, tho larvae are 
few and far between when the moths are most numerous. 
The moths of the third brood lay their eggs at once, and these 
hatch in five or six days ; but the further life history becomes twofold, 
depending on where the eggs are laid. In the insectary the moths lay 
their eggs preferably on young clover he^ds, but if not supplied with 
these they oviposit erratically on fresh or dead leaves or stems. Out- 
of-doors in September and October the larvae occur in two situations; 
either in immature clover heads, or at the crown of the plant. In the 
clover heads active larvae can be found thruout October, in spite of the 
