CLASSIFICATION AND DESCRIPTION OF COMMON INSECTS 207 



Mottled Umber Moth (Erannis defoliaria Clerck). — Destructive 

 in plum and cherry orchards on the Pacific slope. A European 

 insect, resembling the basswood or lime tree span-worm {Erannis 

 tiliaria) . 



Adult. — Appears in November; female wingless, brown, with rows 

 of brown spots; fore wings of male dull ochre-brown, crossed by two 

 dark waved bands; hind wings pale and mottled with brown dots. 



Larva. — Active in June-July; a span-worm, with black stripes sepa- 

 rated by reddish-brown stripes; spiracles in reddish-brown blotches. 



Bruce's Measuring Worm {Rachela bruceata Hulst). — Destructive 

 in New York in 1886 and in Alberta in 1902-3. 



Adult. — Female wingless, 3^^ inch long, light brownish-grey; 

 male winged, expanding i}^^ inches, pale brownish. Oct.-Nov. 



Eggs. — Reddish-orange, oval, finely pitted; laid singly in crevices 

 of bark; hatch in April. 



Larva. — Three-fourths inch long, apple-green, with three narrow 

 yellowish-white stripes along each side of body; head and thoracic 

 shield black; feeds 4 or 5 weeks in April and May, especially on blossom 

 buds. 



Pupa. — -Light brown in a slight silk-lined cocoon in the ground. 

 One generation in a season. 



PsYCHiD^ (Bag-worm Moths) 



Evergreen Bag Worm {Thyridopteryx ephemermformis Ha worth). — 

 Occurs on conifers, red cedar and arbor vitae. 



Adult. — Female wingless, naked and grub-like; male with trans- 

 parent wings. September-October. 



Eggs. — Deposited in a mass within a bag composed of silk mixed with 

 bits of leaf and twig in September-October. They winter over and 

 hatch in May-June. 



Larva. — Feed on the leaves within bags which are gradually en- 

 larged as they mature. 



PupcB. — Formed within the bags. 



Control. — Spray foliage with arsenical solution; gather cocoons 

 and bags. 



PYRALIDINA GROUP 



Families (After Comstock) 



E. Wings not fissured. 



F. Hind wings without a fringe of hairs at base of Cubitus. 



