INSECTS AFFECTING PARK AND WOODLAND TREES 



471 



Three banded clearwing 



^~MemytJirus tricinctus Harris 



A black clearwing moth with three conspicuous yellow abdominal bands lives in the 

 larval stage in Saperda galls on willow and poplar. 



This borer attacks the small trunks of willows and poplars, and the 



moth has been bred from the galls of Saperda con color Lec. It 



occurs in Canada, New England and the Middle States westward to Ohio 



and Michigan. Dr D. S. Kellicott, in writing of this insect, states that he 



took larvae from the branches, suckers and small trunks of the balm of 



Gilead, P o p 11 1 11 s c a n d i c a n s, growing on lowlands along the Niagara 



river below Buffalo. The smaller grubs were sometimes found in the 



sapwood or just beneath the bark, but the larger ones were generally in the 



center or pith of the stems. They cause considerable swellings on the 



small branches, which are frequently as prominent as those made on willow 



branches by a tortrix larva, which he found very abundant in the same 



locality. Dr Kellicott was of the opinion that the adult deposited her eggs 



in the deserted burrows of Saperda moesta Lec, thus permitting the 



young caterpillars to easily gain access to the wood, its home for at least a 



year. The Saperda galls become more enlarged by the attacks of this insect. 



Description. Male. Head black, collar yellow in front and at each side 

 behind ; palpi black, yellow inside towards the tip. Antennae blue black 

 above, ferruginous beneath. Thorax black, with a yellow spot at the base 

 of the fore wings and one on each side posteriorly. Abdomen black, with 

 a slight bluish reflection. Second, fourth and last two segments with a 

 yellow band above and below. Anal tuft black. Legs black, middle and 

 hind tibiae partly orange, the latter yellow inside ; tarsi orange. Fore 

 wings opaque, violet black with a short transparent streak at the base ; 

 inner margin streaked with red at the base, sometimes also along the costa 

 for a short distance; underside yellow at the base. Hind wings trans- 

 parent, with a narrow outer margin and discal mark violet black, as are also 

 the veins. Underside with discal mark and costal margin orange red or 

 same as above. 



Female. Like the male, but with only three yellow bands on the abdo- 

 men instead of four, one on each of the second, fourth and sixth segments. 

 Expanse, male and female, 25-28 mm. Beutenmuller 



