Notolophus leucostigma caterpillar 



How to Study the White-Marked Tussock Moth 



{No-toV -o-phus leu-co-stig' -ma.) 



The eggs are laid by the mother moth in a white mass on her 

 cocoon, in the stimmer or early fall; they do not hatch until the 

 last of the following May. The young caterpillars feed at first 

 on the under side of the leaves; later they destroy the whole 

 leaf, except the main ribs. When nearly full grown many of the 

 caterpillars leave the trees and wander about on the walks and 

 ground. It is supposed that these are the females, and that thus 

 the distribution of the species is ensured. When full grown the 

 caterpillar chooses some crevice in the bark of the tree trunk, 

 or on the lower side of the larger limbs, or, perhaps, on some fence, 

 or side of a building, and here spins a cocoon, out of silk loosely 

 woven with hairs from its own body. Within this cocoon the in- 

 sect transforms to a pupa — yellowish white in color, shaded with 

 black or brown. It remains in the pupa state about two weeks, 

 when it issues from the cocoon, a full fledged moth, the last of 

 July or in August. The male is a pretty insect with mottled-gray 

 and brown wings, which expand a little over an inch . These moths 

 may be found in the day time resting upon the sides of houses. 

 The female is a stout, spindle-shaped creature with no wings. 

 It is supposed that once the female had wings like the male, but 

 that they have been lost through disuse through many generations. 

 She crawls out of her cocoon, and clings to it constantly; she 

 finally lays her eggs upon it, and then dies and drops to the ground. 

 The eggs are laid in a frothy mass, which later hardens, and pro- 

 tects them from the storms of winter. There are from loo to 500 

 eggs in each mass. In early fall these egg masses are very conspic- 

 ous, but the dirt and smoke of the city settles upon them, and make 

 them dark and hard to find in the spring. 



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