ENTOMOLOGICAL SOCIETY. 



terminal shoots. The young larvae feed voraciously upon the tender needles and develop 

 with wonderful rapidity. Some idea of their voraciousness, vast numbers, and rapidity 

 of growth may be gained from the fact that the active larval state lasts but a single 

 week, and during this short time they often strip bare vast forests of tamarack. 



"When mature, they drop to the ground and pass the winter in a dark brown, oval- 

 cocoon spun in the moss or grass beneath the trees. 



So far as we have learned, there is but a single brood of them during the season, 

 and this is quite enough. As it is, the defoliated trees throw out a second set of needles, 

 and are thus enabled to survive one or two attacks, but when they are stripped of their 

 foliage repeatedly the results cannot be otherwise than fatal. One or two natural 

 enemies have been found preying upon the larvse, and it is hoped that they may be able 

 to hold them in check, because it is usually impossible to fight them by any of the modern 

 means of insect warfare on account of the inaccessible nature of the places in which 

 they breed. On single trees they may easily be destroyed by spraying, or even by shaking 

 them to the ground, as they cannot crawl back upon the trees again. 



3. The Tent Caterpillars (Clisiocampa americana and C. disstria). Among the 

 Lepidopterous, or scale-winged insects, none attracted more attention last year than the 

 Tent-Caterpillars. There are two species of these common to this part of the continent, 

 one known as the Apple-Tree Tent-Caterpillar, and the other as the Forest-Tent-Cater- 

 pillar. The latter appeared last year in several parts of the province in vast armies. At 

 one place on the W.C. & B. they were reported in the papers as haviug been in such vast 

 numbers that they stopped a train. And judging from the p;ague of them which I saw 

 on St. Joseph's Island, I am quite prepared to believe the reports. 



A comparative study of the life histories of the two species is of interest. The 

 adult insect in each case is a reddish brown moth measuring when the wings are expanded 

 from one and a half to one and three-quarters inches across. In this stage they have no 

 power of taking food, and live only long enough to provide for the generation to follow. 

 The eggs are laid about the middle of July in ring-like clusters encircling the small 

 twigs, usually from 200 to 300 eggs in each cluster. The eggs of the Clisiocampa Ameri- 

 cana may be distinguished from those of the Clisiocampa disstria by the oval form of the 

 clusters, those of the latter being squarely cut off at each end. In both cases the egg 

 masses are covered with a thick coat of tough varnish which renders them waterproof, a 

 wise provision of nature, as it is nearly nine months before the young caterpillars 

 emerge from them. During the first warm days of spring they make their appearance, 

 and after taking their first meal from the gummy substance which has protected them for 

 the winter they begin to feed upon the opening buds. 



The most striking difference in the two species now becomes apparent in the habits of 

 the young caterpillar. Those of Clisiocampa Americana spin a tent in the nearest large 

 fork of the branch upon which they are hatched. Into this they retire at night, during 

 stormy weather, or when they are not feeding, in warm weather they often repose in a 

 black mass upon the outside of it, leaving it regularly once in the forenoon and again 

 in the afternoon to feed. Each caterpillar spins a silken web along the branch wherever 

 it travels. Thus they never lose their way home although they may forage all over the 

 tree. The caterpillars of the other species do not dwell in tents and are more disposed 

 to lead a wandering life. When young they often march from place to place in single 

 file close procession. From the time they are half grown until they reach maturity they 

 are wonderfully active and move about as if they were in a great hurry and had no time 

 to lose. 



Both species reach maturity in about six weeks, and are then handsome hairy 

 caterpillars, about two inches in length. Clisiocampa disstria has a row of white spots 

 down the centre of the back, which distinguishes it from the other species, in which the 

 white line is unbroken. 



The Forest Tent-Caterpillar is a general feeder, living on a great variety of forest 

 trees and often doing considerable damage in orchards. The Apple-tree Tent-Oater- 

 pillar is not such a general feeder, and is more frequently found on the apple or wild 

 cherry. For the latter it has a particular preference. In our forest plantation where 



