219 



FUMIGATING AT NKillT NOT NECESSARY. 



It is now claimed by a careful experimenter at Los Angeles that 

 fumigating orange trees in the daytime with liydrocyanic aoid gas is 

 just as efficacious as fumigating at night, if sufficient care is exercised 

 in preparing the cliemicals. For this information we are indebted to 

 the California Fruit Grower of September 20. 



HEMLOCK DAMAGE BY THE LARCH SAW-FLY. 



The newspapers during tlie past summer have contained many items 

 conceridng tlie great damage done to hemh)ck timber in Elk and Potter 

 counties, Pa., by an insect which causes the tops of the trees to turn 

 brown over large areas. The insect has recently been determined as 

 the Larch Saw-fly {N'ematus erichsonii), a full acc<mnt of which is given 

 in our Annmil Eeport for 1883, pp. 138-140. Its appearance upon Hem- 

 lock in such destructive numbers in Pennsylvania is entirely new, and 

 considerable damage is to be feared. Nothing satisfactory has been 

 suggested in the way of remedies which are applicable in the forest on 

 a large scale. Spraying with the arsenites is the best that can be done. 

 Sucli extraordinary multiplication of this species is, however, usually 

 followed by corresponding diminution, and it will be encouraging for 

 the Pennsylvanians who are interested in the lumber and tanning in- 

 dustries to remember that since the great destruction caused by this 

 insect in Maine in 1881-'82 it has not attracted so much attention. 



A CLEMATIS ROOT-BORER. 



{Acalthoe cor data.) 



In Garden and Forest for October 21 Mr. J. G. Jack has an interest- 

 ing article on this Sesiid root-borer in the roots of Clematis, accom- 

 panying it by a series of handsome figures from the pencil of Mr. C. E. 

 Faxon. The insect was originally described by Harris in the American 

 Journal of Science for 1839. Mr. Jack reared it in 1890 from an old 

 plant of Clematis rirginiana in the shrub collection of the Arnold Ar- 

 boretum at Cambridge. The moth emerged July 23. The eggs, he 

 states, are deposited soon after the issuing of the moths, and larvt^ of 

 various sizes are found the following June. The male moth is remark- 

 able for possessing an orange anal tuft about as long as the abdomen. 

 According to Harris, the insect feeds upon the common wild Black Cur- 

 rant in addition to the Clematis, in the former case living within the 

 stems. Mr. Jack has not, however, found it in this plant. 



