50 
a slight golden luster, and composed of two lobes; the inner much 
the larger of the two and triangular, the forward angle rounded and 
extending into the cellule; the outer ovoid, and sometimes scarcely 
joined to the other; rest of the wing an orange brown. Posterior wings 
pale fuscous; underside yellowish, with an indistinct, narrow, sinuous 
brownish band across the disk. Head bright orange yellow; anterior 
part of the tufts of the thorax orange brown. Expanse 1.25 to 1.30 
inches. 
There are doubtless other species which have been or will be found 
in Illinois, but these are the only ones known- to me at present as in¬ 
habitants of our State. The following brief notes in reference to other 
species which may possibly be met with when our insect fauna has 
been more thoroughly studied, are given as slight aids in detecting 
others than those described. 
Pl. metallica , Grote. Appears to be the American representative and 
possibly but a variety of PL bractea , w. v. The latter has the anterior 
wings marbled with purplish-brown and gray; the metallic spot large,- 
angulated and golden. Expansion 1.7 inches. 
PL bimaculata , Steph. (u — brevis. Guen).—Head, thorax and abdo¬ 
men purplish-brown; front wings varied with fuscous brown and fer¬ 
ruginous, apical angle rounded. Two silver spots almost equal and 
strongly isolated; the first a u surmounted by a little cresent, thus— 
u ; the second more flattened and broadly oval. Expansion 1.65 inches. 
This genus, as has before been intimated, is very widely distributed 
over the world, almost every country having its representative. Dyaus , 
found in Illinois, is found also in West Indies; gamma , found in Cal¬ 
ifornia and probably in British America, is common in all Europe 
and in Algiers; verruca ranges from Illinois to Brazil. There are also 
other species common to Europe and America, and several peculiar to 
the former. In Cayenne the genus is represented by PL feisthamelii; 
in Montevideo by PI nu; in Cape of Good Hope and Southern Af¬ 
rica by PL angulum and limbirena / in Madagascar by PL anargyra 
and other species; in New Holland by P. argentifera; in East Indies 
by PL siqnata , verticulata , and other species; in Northern Africa by 
PL aurifera. 
The Ural region and Eastern Europe, especially Hungary and Aus¬ 
tria, appear to be represented more profusely than any other section 
of the eastern continent. 
What has already been stated in reference to the habits and charac¬ 
teristics of the larvae of PL brassicce and gamma is, as a rule, true of 
the larvae of the other species of the genus. They are attenuated in 
front, have but two ventral feet and hence loop in walking; and live 
exposed on the plants on. which they feed. Many of them are gene¬ 
ral feeders, while others are confined to a single species or genus. 
The cocoon is usually very loose and composed of finest silken threads. 
The larvae of PL modesta , a European species, feeds on the leaves 
of Pulmonaria angustifolia , and appears in April and May; that of 
PL gamma appears in April, June and August, is a very general feeder 
on low plants; PL iota feeds on nettle, archangel, burdock, etc. Pl. 
interrogationis on Urtica urens\ Pl. chrysites on nettles, burdock, this¬ 
tles, etc. Pl. orichalcea. on hemp agrimony ( Eupatoriuin cinnabrium)\ 
PL festucae on bulrush ( Pypha latifolia) ; and PL balluca on the hop. 
Pl. simplex feeds on nettle, burdock, etc. 
4 
