1865.] Science in Canada. 519 



of which a translation appears in the ' Canadian Naturalist,' is ex- 

 tremely interesting ; and is rich in information concerning the dis- 

 tribution of plants throughout that part of the province round Lake 

 St. John, and adjacent to Hudson's Bay. It also furnishes a good 

 general description of the district, which is but little known. The 

 lists of plants include many well-known British species, whilst the 

 number of genera foreign to Britain is extremely small. 



Entomology. — Pieris rapce. — Mr. G. J. Bowles, Secretary to the 

 Quebec branch of the Entomological Society of Canada, read a paper 

 before the branch Society " On the Pieris rapas (or Pontia rapae)," 

 which is the small white cabbage butterfly, common in England, 

 where it is very destructive. He states that it is now present in con- 

 siderable numbers within a radius of about forty miles round Quebec. 

 It appears to have been first introduced into the province at that city 

 about seven or eight years ago, being probably brought over amongst 

 vegetable produce. Two males of a bright canary colour, a variety 

 occasionally taken in England, have been captured. In the autumn 

 of 1863, the ravages of the larvas, in the vicinity of Quebec, were 

 very great. Several specimens collected by Mr. Bowles showed that 

 they are attacked by a parasite, probably one of the Ichneumonidaj. 

 (This is also the case in Britain.) Mr. Bowles describes the insects 

 in order that farmers and gardeners may recognize and destroy them. 



Entomological Society of Canada. — This Society has resolved to 

 prepare and publish catalogues of all the known Canadian insects ; 

 commencing with the Coleoptera and Lepidoptera. This is an 

 example well worthy of imitation by all local and provincial Natural 

 History Societies. 



Attacus polyphemus. — In August, 1863, Mr. Wm. Couper, of Quebec, 

 found two caterpillars of this lepidopter feeding on sweet-briar, 

 a plant said to be introduced into Canada. The food-plants pre- 

 viously ascribed to it, were the oak, elm, and lime trees. It has 

 also been found on the maple ; but as the larva is large, soft, thin- 

 skinned, and hairless, its occurrence on the thorny briar is remarkable. 

 Mr. Couper kept the two specimens in confinement on this plant, until 

 they commenced spinning, previously to which, they ejected the 

 contents of the viscera, consisting of about a teaspoonful of a dark 

 green fluid. 



Gall of Triticum repens. — The same observer describes the occurrence 

 on Triticum repens, Linn, (the creeping wheat-grass or couch-grass), 

 of a gall produced by a hymenopterous insect of the genus Eurytoma 

 (possibly E. fulvipes). The insect appears in June, when the female 

 deposits an egg in each joint of the grass, producing a gall, which 

 appears externally as a tumid part of the stem. As soon as the larva 

 issues from the egg, it places its head downwards in the gall, remain- 

 ing in that position until it eats its way through. During the winter, 

 it remains torpid in the hardened gall, becoming active again in the 

 following spring, and changing to the perfect insect in time to attack 

 the young grass. 



