i7« 
TRANSFORMATIONS OF INSECTS. 
segments. It is very injurious to cereal crops. When the wheat 
crop is about to ripen, if some white ears are seen elevated above 
the others which are heavy, green, and somewhat bent, there is 
a tolerable certainty of not finding the grains but of discovering 
one or more larvae of Cephas pygmcens. These small white larvae 
may be exposed by breaking the white ears, and they live in the 
powdery dust which they have produced by gnawing the corn, 
and by their dejections. These larvae appear to have a strong 
impression that the wheat ear is all very well for a temporary 
home, but that it is dangerous for a permanent one, for before the 
Sirex gigas. 
harvest the insect crawls down the stem and buries itself in the 
ground near the roots. There it makes a cocoon, and hybernates 
through the winter, out of the way of sickle and scythe. 
The Swicidce are a more numerous family than the last, 
and they may be known by their long bodies and short thick 
mandibles ; the antennae being thread-like. The principal genus 
is Sirex . The females of it have a long, straight saw, which is 
toothed, for it has to pierce something harder than leaves and 
rose twigs. The species are more common in Germany, Northern 
Europe, and North America, than in southern districts ; and 
they frequent the forests of firs and pines. The great Sirex — 
Sirex gigas — is a splendid insect : the female is black and yellow, 
