ANNUAL MEETING. 39 



males Hying at Cambridge, Massachusetts, during the months of December and 

 January, improving the warm sunshine that they might sally forth in search of 

 a mistress. The females, after celebrating their nuptials, deposit their regular 

 egg-clusters (fig. 4, e), generally on the branches of their food plants, though I 

 have taken them at Cambridge from oif the fences underneath the magnificent 

 elms, for which that city is so noted. These egg-clusters arc covered with a 

 glue that they may the better resist the cold and damp. Thus the eggs of the 

 vernata may be seen from February till May, while those of pometaria will be 

 be found from October to May. 



So far as 1 know both species issue from the eggs as larva; (sec fig. '■), x, and 

 4,/), about the same time — a little prior to or at about the period that the ap- 

 ple leaves burst forth. I think, too, that there is little difference in the length 

 of time which they remain as larvae. Thus both species may be found doing 

 their ruinous work from some time in May till late in June. From the above- 

 it will be seen that vernata remains as a chrysalis much longer than does pome- 

 taria — from July to March, instead of from July to October. The dates then 

 are as follows : Vernata — imago in March, eggs from March till in May, larvae- 

 in May and June, chrysalis (see fig. 4, g), from July till March. Pometaria — 

 imago in October, November, December, January, and perhaps later, eggs from 

 October to May, larva? same as in vernata, while the chrysalis may only remain 

 from July to October. 



HABITS OF THE CANKER "WORMS. 



As the female moths issue from the grouud, they are impelled by instinct to 

 seek such a position for their eggs that the larva? when they escape from their 

 egg-prison may find suitable food near at hand, hence they strive to attain to- 

 the branches of those trees that will in due time afford the desired pasturage for 

 the to be larvae. But as her ladyship has no wings she must needs crawl up the 

 trunk of the tree. This feat accomplished, the vernata with her ovipositor 

 commences to obtrude her oval eggs, to the number of 100, more or less, under 

 the loose bark, etc., while pometaria places her even greater number of trunc- 

 ated cones, in regular order, anywhere upon the branches. The moths have 

 been usually regarded as nocturnal, though according to Dr. Le Baron the ver- 

 nata is more properly crepuscular. At least he found them most active in 

 early evening, when the wingless moths fairly thronged the tree trunks in their 

 eagerness to reach the desired situation for egg-deposition. This was in the 

 middle of March. Later in the evening he found them far less active. The 

 males of both pometaria and vernata are often seen on the wing during the day. 

 Yet they seem to have learned the proper time for courtship, as they come 

 eagerly forth to act as escorts and play the gallant to the females as the latter 

 take their evening stroll in the quiet twilight. In May, as soon as the eggs 

 hatch, the wee larvae — almost microscopic in size — commence depredations by 

 eating holes in the young tender leaves. The foliage soon appears as if scorched, 

 suggesting the appropriateness of the term canker-worm. Later if the larva? are 

 very numerous, as they are wont to be, the entire foliage is consumed, leaving 

 little to be seen except the midribs of the leaves. 



Ever and anon the larva? will fall from the tree, hang suspended by a silken 

 thread they spin for the occasion, and swing to and fro as they are borne by the 

 wind ; and often if the wind is strong, they are carried to other trees. When- 

 ever they are jarred they will thus prepare for a swing. Whether they ever do 

 this "simply on pleasure bent" anticipating the pleasing sensations of a delight- 



