INSECTS AFFECTING PARK AND WOODLAND TREES 39I 



it infests green bark on living injured and d)ing hemlocks, the beetles 

 occurring the latter part of March and during May, June and July. He 

 also adds that it has caused the death of a great nunii^er of hemlock trees 

 in that State. Dr J. B. .Smith records this insect on both spruce and 

 hemlock in W-\v Jersey. 



Distribution. This species occurs throughout the middle and northern 

 part of the United States, being very abundant about Lake .Superior, 

 according to Dr LeConte. It has been taken by .Mrs .Slosson on 

 Mount Washington, and occurs in limited numbers in southwestern 

 Pennsylvania. 



Natural enemies. A single parasite, B r a c o n ]> e c t i n a t o r Say, was 

 bred by .Messrs Riley and Howard from cocoons found in the larval mines 

 of this insect. 



Red cedar bark beetle 

 Plilocosinns doit at its Say 



.\ liglu brown or black beetle, about '/,6 inch li^ng, makes peruliar rliibbcd, longi- 

 tudinal galleries under tiie bark of red cedars. 



This little beetle can hardly be classed as ijijurious in the .\dirondacks, 

 since it was found by the writer in comparatively small numbers only in 

 dying or dead limbs. It was taken by him Aug. 21, i goo," at Floodwood, 

 from limbs cut the preceding June, as nearly as could be ascertained. The 

 beetles were just beginning their operations at this time. 



This insect was also found in small ninni)ers in the dying red cellars at 

 Axton. It is evidently a common species in northern New York, because 

 almost all red cedar used in the ccinstruction of rustic sinnmerhouses and 

 similar structures is very prettily grooved by the characteristic burrows of 

 this insect. 



Early history. Dr Packard states that this is a common species on 

 junii)ers about the cit\- of Providence R. I., where its attacks are confined 

 to sickly or dead trees. The beetles were found alive in their burrows 

 May 12 antl 13, and also nearly full grown larvae but no pupae. He has 

 found this insect in considerable numbers in northern Maine under the 



