56 



is distended, that protracted flight would appear almost impossible, and by the time the 

 eggs are deposited she is exhausted and incapable of much exertion. The male, however, 

 flies strongly and with great swiftness. Some years since a balsam poplar growing in 

 front of my windows was badly injured by this insect, which along with Saperda mcesta, 

 killed it in a few years. Upon one occasion, early in the afternoon, a male flew from? 

 the tree, although the sun was shining brightly at the time ; it appeared, however, to be- 

 confused, as it settled on the road about twenty feet from the tree. 



Immediately after sunset the males made their apearance, flying swiftly up and down 

 the street ; after dashing past the tree a few times they would circle around it, and finally 

 make their way up amongst the limbs at their junction with the trunk, where no doubt 

 the females were resting. On several occasions females were attracted by light, blunder- 

 ing in with a heavy labouring flight ; the males appeared to be indifferent to it as none 

 entered the house. 



Dr. Fitch states that this is a most prolific insect, a specimen that he obtained 

 having extruded upwards of three hundred eggs within a few hours of its capture. The- 

 eggs are of a broad oval form and about the size of a grain of wheat, being the tenth of 

 an inch in length and three-fourths as thick, of a dirty white color with one of the ends, 

 black. When highly magnified their surface is seen to be reticulated or occupied by 

 numerous slightly impressed dots, arranged in rows like the meshes in a net. From 

 observing her motions in confinement I think the female does not insert her eggs in the- 

 bark but merely drops them into cracks and crevices upon its outer surface. They are- 

 coated with a glutinous matter which immediately dries and hardens on exposure to the 

 air, whereby they adhere to the spot where they touch. (Fitch.) As soon as hatched 

 the young caterpillar burrows into the tree, at first feeding upon the soft inner bark, 

 but as it grows it sinks deeper, finally penetrating to the solid heart wood. When about 

 to assume the chrysalis form it changes the direction of its burrow, working outwards 

 until it reaches the bark, lining the passage with silk, then going back a little distance it 

 spins a cocoon and changes to a chrysalis. The caterpillar is of a reddish color above,, 

 the head is black, while before pupating it changes color to white, tinged with pale 

 green. When fully grown it measures two inches and a half or more in length and is. 

 nearly as thick as the end of the little finger. (Harris.) 



The chrysalis is an inch and three-quarters long and is of a chestnut color, the fore- 

 part darkest. On the upper side of each segment of the abdomen there is a row of tooth- 

 like projections, by means of which when about to disclose the moth, the chrjsalis pushes- 

 itself forward until partly out of the tree. The moth now ruptures the chrysalis and 

 creeps out, leaving the empty shell sticking in the mouth of the burrow. 



As it is very difficult to see the moths when resting on the trees, any attempt to re- 

 duce their number by handpicking would be useless, but coating the trunks with soft soap 

 in the early part of June would probably prevent the moth from laying her eggs on them, 

 and any tree known to be badly infested should be cut down and burnt. Another species, 

 the Xyleutes querciperda of Fitch, also attacks the oak but appears to be much less com- 

 mon than the robinise. 



2. The Thunderbolt Beetle, Arhopalus fulminans (Fabr.) Order Coleoptkra ; 

 Family Oerambycid.e. 



This pretty beetle is blackish brown, with slight dark-blue reflections ; the legs and 

 antenna? are of the game colour, the latter being scarcely longer than the body. The top 

 of the head and the sides of the prothorax and under side of the body are covered with pale 

 gray pile, while certain silver markings on the wing-cover are composed of similar close- 

 set fine hairs. The hairs on the sides of the prothorax enclose a conspicuous black spot, 

 while the top is black and more closely punctate than the wing-covers. The latter are 

 each crossed, by four acutely zigzag lines composed of microscopic hairs, forming W — like 

 bands on the elytra ; the basal lines being less distinctly marked than the others. The 

 ends of the wing-covers are also tipped with gray, especially on the inner side of the end. 

 The legs are pitchy brown with light hairs, and with a reddish tinge on the terminal 

 joints (tarsi). It is a little over half an inch long. (Packard). 



