INSECT NOTES. 143 



case-bearer uses a bit of dried spill from the larch for its case 

 and from this protection it extends its head and thoracic feet 

 when it wishes to move about or feed. Along the ventral side 

 the spill is split and pieced together with silk woven by the tiny- 

 caterpillar. As it grows it weaves an extension of this silk on 

 the anterior part of the case. The full grown caterpillar is 

 about 3 millimeters* in length. The case measures 4 millimeters 

 or 5 millimeters. The caterpillars are much more active during 

 warm and sunny weather, and during cold days they do no 

 feeding. When fall comes on the nearly grown caterpillars in 

 their little spill cases attach themselves to the bark and about 

 the bud angles and live dormant for the winter. With the first 

 warm days of spring the caterpillars become active and feed 

 upon the soft tender larch needles. As the caterpillars are 

 nearly full grown this is their most vigorous feeding spell and 

 as the larch needles are eaten when they first begin to grow, it 

 is a particularly hard season of the year for the tree to endure 

 such an attack. The same number of case-bearers later in the 

 season would by no means create so much damage. 



The full grown caterpillars do not leave their cases but attach 

 them to the twig or commonly in the cluster of needle-shaped 

 leaves where they are not easy .to find and let the cases serve 

 for a cocoon. 



The moth. In the vicinity of Orono the adult insect emerges 

 about June 4. They are a glistening ash gray in color. The 

 wings are slender and the hind wings have the deep delicate 

 fringe common to this group of moths. It expands about 9 

 millimeters. This moth is something the shape of the common 

 clothes moth and a little smaller. The female deposits the eggs 

 in among the larch needles and the young naked caterpillar eats 

 its way into a needle and after disposing of the soft interior as 

 food, uses the empty shell for its case. 



There is fortunately but one generation a year. Observa- 

 tions upon these case-bearers about Orono had been made dur- 

 ing 2 seasons when Dr. James Fletcher, Central Experimental 

 Farm, Ottawa, published his interesting account of the appear- 

 ance of the Larch case-bearer, Coleophora laricella, in Canada 

 (Report 1905). Doctor Fletcher kindly compared specimens 

 bred in Maine with the Canadian Coleophora and pronounced 

 them undoubtedly the same species. Ratzeburg in his Forst- 



* One inch nearly equals 25 millimeters. 



