Sphingidae 
of which, as examined under the microscope, is seen to be quite 
different from that which prevails in any other family of moths. 
The accompanying illustration (Fig. 20) shows this arrange¬ 
ment in the case of the common Five-spotted Hawkmoth, 
(Protoparce quinquemaculatus). 
The wings are small in comparison with the body. The 
front wings are very long in proportion to their width, and 
the costal veins are always very stoutly developed. The tip 
of the wing is usually pointed, and the margins are straight 
or evenly rounded, though in some genera, principally be¬ 
longing to the subfamily Ambulicince , they have undulated 
or scalloped margins. The hind margin of the fore wings 
is always much shorter than the costal margin. The hind 
wings are relatively quite small. The venation of the wings 
is characteristic. The primaries have from eleven to twelve 
veins, the secondaries eight, reckoning the two internal veins, 
veins 1 a and 1 b , as one. Veins eight and seven are 
connected near the base of the wing 
by a short vein, or bar. The discal 
cell is relatively quite small in both 
wings. There is always a frenulum, 
though in the Ambulicince it is frequently 
merely vestigial. The general style of 
the venation is illustrated in Figure 2. 1, 
which represents the structure of the 
wings of Sesia tantalus Linnaeus. The 
hawkmoths have prodigious power of 
flight. A few genera are diurnal in their 
habits; most of them are crepuscular, flying in the dusk of 
evening, a few also about dawn. 
The larvae are usually large. There is great variety in their 
color, though the majority of the North American species are of 
some shade of green. They usually have oblique stripes or 
their sides, and most of them have a caudal horn, which in the 
last stages in some genera is transformed into a lenticular 
tubercle. In a few genera the anal horn is wanting. The 
anterior segments of the bodies of the larvae are retractile. When 
in motion the body is long and fusiform, but when at rest the 
head and the anterior segments are drawn back, the rings 
42 
Fig. 21.—Neuration of 
wings of Sesia tantalus 
Linnaeus. 
