^0 ENTOMOLOGICAL SOCIETY OF ONTARIO. 



1884, he summed up the condition of the larches as follows, and he thinks that the pre- 

 diction therein contained, was almost verified in 1885 : " On the whole, then, while a 

 small proportion of larches have been killed by this worm, this vigorous tree, though de- 

 foliated for two successive summers, seeras, in the majority of ca es, to survive the loss of 

 its leaves, though it threw out much shorter ones the present summer. Possibly 10 per 

 cent, of our northern larches died from the attacks of this worm. Very probably the 

 numbers of this insect will diminish during the next year, and the species may ultimately 

 become as rare as it has always been in Europe." 



The maximum of damage having been committed, and the supply of food having been 

 correspondingly diminished, have probably led to an arrest in the further development of 

 the insects, and their numbers may continue to decrease. It will be, however, many 

 years before th« districts ravaged by them regain their wonted luxuriance of vegetation, 

 and the larch forests which they have destroyed will in many instances be replaced by 

 spruces (Maritime Provinces) cedar (Quebec) or other trees which may find the vacated 

 localities suitable for their propagation. 



In the paper by the Rev. Mr. Fyles, already mentioned, he gives some figures to 

 show the amount of injury done in the one Township of Bury, in the County of Leanox, 

 Quebec, and an application of these estimates for one square mile, to the extended areas 

 of trees destroyed in the several Provinces, will give some idea of the actual money value 

 of the damages inflicted upon our possessions by this unwelcomed immigrant. "As we 

 have seen, there are in Bury 6 40 acres of tamarack, giving on an av^erage forty market- 

 able trees to the acre, or 25,600 such trees in all. Every tree contains at least 400 feet, 

 board measure, of lumber. This gives for the whole forest 10,240,000 feet, which, in a 

 sound condition, would have been worth $30,720," at $3 per 1,000 feet on the stump, 

 " and which left standing, would, under favorable circumstances, have been increased in 

 value." He places the total loss to the township at $50,000, and to the adjoining Town- 

 ship of Lingwick at double that sum, and in consideration of the wide extent of the in- 

 sect's depiedations, he comes to the conclusion that " Nemahts Erichsonii has been the 

 worst insect pest that has ever visited the Province of Quebec." Regarding the re-growth 

 of the trees, he adds : " The tamarack forest of the Townships is a thing of the past. 

 There seems to be a laiv of nature, that, when one growth of trees is swept away, another 

 of a diflferent kind shall succeed it. The hemlocks and pines of our mountain sides give 

 place to the poplar and the white birch. The tamaracks will probably be succeeded by 

 the American arbor-vitas, or white cedar [Tliuja occidentalis. ) And, if there were no such 

 natural law, the world is too old, its population too vast, and land in the temperate 

 reoions too valuable, for us to suppose that large tracks of lowlands will be left in a state 

 of nature for 200 years to come." 



Although this insect has probably come to us from Europe, it is not there the same 

 prolific pest which it has become under the stimulus of our more extensive tamarack 

 forests, a change of climate, and, perhaps, escape from hereditary parasitic foes. It was 

 described and named in 1838, and Cameron gives its continental distribution as Sweden, 

 Denmark, Prussia, Holstein, Harz, Bohemia. Holland and France. The only country in 

 which it is reported as injurious is Germany. In Great Britain " it does not not seem 

 to be a common species. I have only seen a specimen taken by the Rev, T. A. Marshall, of 

 which I do not know the locality. Mr. Dale records it from Glanville's Wootton." Its 

 uarasites are given as Perilissus Jilicornis and Pteromaliis Klugii, Rtz. The former genus 

 has not been recorded from America, but the latter species may possibly be identical with 

 the parasite of which D. Packard bred considerable numbers in 1882, and to which he 

 gave the provisional name of P. nematiclda. 



For descriptions of the insect and further information as to its habits, reference can 

 be made to the excellent paper by Mr. Fletcher in Ann. Rept. No. XV. Cameron states 

 that the male is unknown, and from all the larvoe we have bred there has not emerged a 

 single male, I have, however, one male, taken in a tamarack swamp on the 15th June, 

 1889, which seems to belong to this species, differing from the female chiefly in having 

 the antennre, except two basal joints, and posterior legs almost rufous, and the sides of 

 prothorax almost white. 



