578 



willows and climbers in Quebec and Montreal during August. The 

 egg-masses are laid on the empty pupal cases attached to the bark of 

 the trunks and branches. 



Boring insects include the Cerambycid, Plagionotus speciosus (sugar 

 maple borer), the eggs of which are deposited in the bark, the resulting 

 larvae boring into the sapwood. The pupal chamber is constructed 

 at the approach of the second winter close to the corky tissue, and in 

 the following summer the newly developed adult breaks through the 

 thin covering of bark. As the tunnels are mostly vertical, some of 

 the cortical surface dries up and falls, leaving bare the adjacent ligneous 

 layers. The Buprestid, Agriliis auxins (bronze birch borer) is a recent 

 introduction. Many larvae can be found making a labyrinth of 

 tunnels in a single tree, which is killed within two or three years. 

 The larva lives one year, and the adult escapes from the tree in the 

 following spring. The Cerambycid, Saperda calcarata (poplar borer) 

 is one of a number of poplar borers. The tunnels are made vertically 

 in the sapwood. The larva takes three years to develop. The weevil, 

 Cryptorrhynchiis lapathi (poplar and willow borer) was introduced 

 some ten years ago, probably from Ontario ; it attacks for preference 

 Carolina poplars, which it frequently kills one year after they are 

 planted. 



Essential measures for the preservation of these ornamental trees 

 are clean cultivation, removal of diseased portions and cleaning of the 

 bark. Wood borers can be exterminated with carbon bisulphide, and 

 arsenical solutions should be applied for caterpillar epidemics. In 

 spring and autumn, eggs and cocoons should be collected and immedi- 

 ately burnt. Bands covered with an adhesive applied to the trunks 

 will protect the trees against many caterpillars. 



Treherne (R. C). The Control of Insects liable to be imported in 

 Railway Cars. — Canad. Ent., Orillia, \\\\ no. 6, June 1922, 

 pp. 121-128. 



From an examination of statistics it is evident that 85 per cent, 

 of the codling moth [Cydia pomonella, L.] infestation in British 

 Columbia is due to importation either by infested railway cars or 

 infested fruit, the former being the more important of the two. In 

 spite of the willing cooperation of the railway authorities the present 

 method of inspection is inadequate in preventing spread by this 

 means. Various methods of treating the infested cars have been 

 tried, with the result that heat is considered the most satisfactory. 



The experiments described show that the larvae and pupae may be 

 readily destroyed by steam heat in the ordinary refrigerator car in 

 fifteen minutes with a final registration of 160° F. with or without ice 

 in the bunkers. Provided that the car is in good repair no damage to 

 the insulation will take place. 



Hopping (R). Coniferous Hosts of the Ipidae of the Pacific Coast and 

 Rocky Mountain Regions. — Canad. Ent., Orillia, Yiv, no. 6, June 

 1922, pp. 128-134. 



An accurate knowledge of the food-plants of Scolytid beetles is 

 most important, particularly as it is highly probable that under endemic 

 conditions certain species will confine their attacks to one species of 

 tree, whereas under epidemic conditions they will attack any of the 

 trees on which they are known to breed. Certain genera are even 

 confined to certain generic groups of trees. In California the genera 



