120 GIANT SILK-WORMS. 
row of black spots, the latter with a row of four black spots 
and one spot near the base of the wing. The hind-wings of 
male are whitish with a small black discal spot, a terminal 
row of spots and a dusky patch at hind angle; in the female 
the hind-wings are dusky. Expanse, 38-43 mm. 
The curious caterpillar is shown in Fig. 120; the moth 
in Fig. 121, Plate XIX. 
Ne ad ane 
Fig. 120.—Cerura borealis Bdv,caterpillar. After Packard. 
FAMILY SATURNIIDZ OR GIANT SILK-WORMS. 
Among this family we find the giants of North American 
moths, some of them expanding four inches and more; in the 
tropics they are represented by moths that have a spread of 
wings sometimes fully twelve inches. The larve of all spin 
more or less bulky silken cocoons, and are interesting on 
that account as the silk could be made of use, being very 
strong. Formerly the genuine Chinese Silk-worm was 
classed among these insects. 
THE CECROPIA SILK-WORM. 
(Attacus cecropia Linn.). 
The great size and peculiar coloration of this large silk- 
producing caterpillar (Fig. 122) makes it an object easily 
recognized. It is nearly four inches long, of a pale limpid- 
green color, and as thick as a man’s thumb. It bears on the 
third and fourth segments large warts or tubercles of a 
coral-red color, which resembles small ripe strawberries; the 
other tubercles on the back of the caterpillar are smaller 
and yellow, excepting those on the last segments which are 
blue. 
