1090 
MEGALOPYC4E. By Walter Hopp. 
nierpunc- 
tosa. 
alydda. 
nigella. 
isabela. 
mi da. 
Additions. 
On p. 1083, insert after M. dyari: 
M. interpunctosa Dogn. (described as Mesoscia) is allied to dyari and may likewise be regarded merely 
as a race or differently coloured form of alydda Drc. The o has a blackish ochreous head, thorax and abdomen 
the greenish yellow forewing with a series of black internerval spots; hindwing light ochreous. Colombia, Tolima. 
M. alydda Drc. (described as Alpis) (161 c). The silky brown forewing with a blackish costa and black 
basal spot are separated from the light distal margin by black, outside whitish, spots. Hindwing light yellow¬ 
ish. Head, thorax, abdomen and legs brown. Costa Rica, Ecuador, Peru. — Dognin describes another 
Colombian form with a different colouring, of which only the $ is known: — nigella (described as Norape) with 
blackish or dark grey hindwings and isochromatic or olive brown colour. Colombia: Tolima. It may be that 
nigella represents merely the $ of interpunctosa. 
On p. 1085, insert after N. jaromillo Dogn.: 
N. isabela sp. n. (161 c). Head yellow, thorax, abdomen and legs yellowish white, the forelegs brownish 
on one side. Forewings ochreous, all the veins ruled with broad white lines. Hindwing yellowish white. Peru: 
Oconeque, Carabaya (G. Ockenden). Type in the Tring Museum. 
II. Megalopyginae. 
The Megalopyginae , as we have already mentioned, are not to be separated into genera and species 
in the same sense as the Trosiinae, because the appendages of the 10th and 9th segments of the male abdomen, 
which form stages of development in the Trosiinae, have stopped on the very same point of organizatory devel¬ 
opment ill the Megalopyginae. Whatever remains of sexual-morphological differences of the must be 
used with the same caution for the distinction of the species as other differences, the neuration, marking and 
colouring, hair and scales. On the whole, these differences are scanty, and not always indubitable as regards 
constancy. Accordingly also the species are partly very closely allied to one another, and the whole of the 
Megalopyginae exhibit quite closely contiguous elements of marking and colouring. Another difficulty for 
the determination of the species is the extraordinary variability of widths according to the size of the indi¬ 
vidual insects, the width of the wings, the length of the antennae, of the colourings and the markings produced 
by them. This variability of widths is presumably caused by the single individuals having different lengths 
of life as larvae. Especially the full-grown larva can, according to observations, immediately proceed to its 
pupation or remain for many months (up to 18 months) unpupated in the spun cocoon, whilst the pupal stage 
seems to be confined to a time of about 4 weeks. In this way all the stages of development are to be found 
throughout the year, particularly in the districts without definite rainy seasons. Whether the larvae feed during 
the dry or rainy seasons, is of great influence upon the size of the individual insects and upon the development 
of pigments. In this connection is also the formation of decidedly melanistic specimens. Moreover, the GS 
and 9? °f the Mealopyginae sometimes differ considerably in colouring and marking. Finally, the $<$ are 
sometimes observed to approach individually the 9$ in colouring and marking, the 99> however, to approxi¬ 
mate the male marking and colouring; thus are produced gynomorphous $<$ and andromorphous 99’ an( t in 
extreme cases occur individual insects which, from the antennae ( 9 from more feebly pectinate to plain) to 
the anal hair (9 distinctly curled hairballs) are completely GS on one side and 99 011 the other side {Meg. lanata). 
We divide the Megalopyginae into two genera, Megalopyge Him. and Podalia Wkr. They differ in the 
of Megalopyge lacking the retinaculum of the frenulum, whereas in Podalia it is developed. The numerous 
other genera that have been established cannot be maintained owing to the inconstancy of the marks of dis¬ 
tinction used. Thus belong to Megalopyge: Gasina , Alpis, Zebonda Wkr., Ghrysopyga, Ochrosoma H.-Sch., 
Qylothrix, Pimela Clem., Lagoa Harr., Cyclara Schs. To Podalia Wkr.: Gois , Malmis, Bedalia, Unduzia Dyar. 
1. Genus: Megalopyge IIbn. 
Nuda- group. 
M. nuda Stoll {— partheniata Dyar) (161 c). Wings scantily scaled, the veins on the forewings with 
fine black lines on both sides, but only those proceeding from the cell-end extend to the distal margin. Fine 
black streaks between the veins. Hindwing with fine black hair on the veins. The 9 has the same, but some¬ 
times much darker ground-colour on the wings. The other colourings are very variable: head, thorax, abdomen 
