1910 ENTOMOLOGICAL SOCIETY. 63 



liminaris, injures living trees by driving short tunnels into the bark through which 

 the sap flows copiously, later to harden and form the gummy masses which char- 

 acterize the work of P. liminaris and E. riigulosus in healthy bark. This species 

 attacks the apple, cherry and peach, and is often found working with P. liminaris 

 in the same limb. The three washes mentioned above are also useful against this 

 species 



Clean culture is absolutely essential if these borers are to be controlled. 

 Diseased and dying fruit trees furnish breeding grounds for these beetles and for 

 numerous other insect pests, and should be burnt to prevent the spread of the insects 

 beneath the bark and in the wood. 



The following key will enable anyone to separate quite easily the three forms 

 discussed. A hand-lens is needed for examining the antennse, but the other 

 characters are visible to the naked eye. The beetles are easily distinguished by 

 their tunnels, as indicated by the diagrams. 



A. Venter of the abdomen with the caudal portion bent abruptly dorsad. An- 

 tennal club flat and marked by angulated sutures. (Bark-borers) Eccoptogaster 

 rugulosus (The Fruit-tree Bark-beetle). 



AA. Venter of the abdomen normal, regularly curved. 



B. Antennal club lamellate, of three separate, laterally produced segments. 

 Head visible from above. (Bark-borers) Phloeotribus liminaris, Harris. (The 

 Peach-tree Bark-beetle). 



BB. Antennal cliib globular, truncate at the tip. Head deeply imbedded in 

 the prothorax, the anterior margin of which is nearly horizontal, invisible from 

 above. (Wood-borers, tunnels stained deep black). Xyleborus dispar, Fabr. (The 

 Shot-hole Borer), 



OBSEEVATIONS ON ONTARIO INSECTS IN 1909. 

 By C. J. S. Bethune, Ontario Agricultural College, Guelph. 



As Mr. Gibson and Mr. Caesar have already presented reports upon the insects 

 of the season, it only remains for me to refer to some that have especially come 

 under my observation, or that have been a source of trouble to many corres- 

 pondents. 



The weather during spring and early summer seemed peculiarly favour- 

 able to the multiplication of Plant-lice (Aphids). They were to be found in more 

 than usual abundance swarming upon a great variety of trees, shrubs, and plants, 

 and causing a great deal of injury by checking the growth and impairing the vitality 

 of everything they attacked. Cabbage and turnip plants were affected by them 

 early in the season, but they ceased in most cases to be much trouble later on, in 

 marked contrast to last year when they were a very serious plague till the frost 

 came and destroyed them. In the vegetable garden peas, potatoes and lettuce were 

 especially attacked and in the flower borders roses, asters, hollyhocks, etc., and 

 even ferns; currant bushes had their leaves covered with wart-like swellings be- 

 neath which swarms of aphids were huddled; plum and cherry trees showed signs 

 of the intruders by the crinkled and twisted leaves at the ends of the branches 

 enclosing multitudes of black lice; on the leaves of apple trees green aphids were 

 al)undant, while twigs were soft and foliage tender, but later on they migrated to 

 more succulent plants, probably to the wheat fields. Many elm trees looked sadly 

 out of sorts from shrivelled and distorted leaves covered with disgusting woolly 



