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Pin-holes in poplar wood. — January 20, I received from Pickeua, 

 W. Va., a piece of souud yellow-poplar wood containing an example 

 of Xyleborus puhescens Zimm,, which served to explain the cause of a 

 serious trouble complained of in pojilar lumber, sometimes causing 

 the loss of thousands of dollars to poplar manufacturers. It appears 

 that the beetle is either in the log when the lumber is sawn or it 

 enters the lumber directly after it comes from the saw. It continues 

 to work in it for some time after, boring it full of minute pin holes, thus 

 reducing the value of the lumber. Xyleborus puhescens is a remarkable 

 insect in its habits and distribution. It appears that it will infest the 

 wood of all kinds of trees, and that it is widely distributed over the 

 world. It is probably the same species as the one which is so destruc- 

 tive to sugar-cane and wine casks. It is my belief that Zimmerman's 

 name and a number of other names given to slightly varying forms of 

 the genus must give way to WoJlaston's name applied to the species 

 he described in 1857, now known as Xyleborus perforans Wall. 



On February 3, Prof. Eane called my attention to swarms of small 

 " gnats " in the station greenhouse. Upon examination I found that 

 they were Braconid parasites of Aphis hrassicce^ Avliich was very abun- 

 dant on the radish and lettuce leaves. I also found that the method 

 the gardener was using to destroy the lice, i. e. smudging with sulphur 

 and tobacco, was killing the parasites as well. Realizing the opportu- 

 nity offered for an experiment to determine the value of the parasites 

 as a natural check against the Aphides, I requested that the smudge 

 treatment be discontinued. The experiment proved to be a complete 

 success. Within a few days we could see that the parasites were gain- 

 ing on the Aphides, and within two weeks the numbers of the latter 

 were greatly diminished and had ceased to be particularly injurious, 

 and they were kept under control by the Braconids until all the vege- 

 tables were removed from the house. Specimens of the Braconid were 

 sent to Mr. Ashmead, who pronounced it a new species and named it 

 Aphidius lactuc(e n. sp. If this insect makes its apj)earance next 

 winter in the greenhouse, we will attempt its introduction into other 

 greenhouses as a method of combatting this serious hothouse pest. 



The clover-leaf iceevil. — On April 18, we received specimens of the 

 larva of the clover-leaf wee\il [Fhytonomiis pmictatus) from Berkeley 

 and later from Hampshire counties, W. Va., with the statements that 

 the clover in that section of the State was being destroyed by the 

 insect. Upon investigation, on May 1, I found tlie fungus epidemic 

 had struck them a few days previous to m}" arrival, and the leaves of 

 the clover, the dead weeds, etc., were covered with the dead and black- 

 ened bodies of the larva?. Scarcely a living example of the insect 

 could be found. 



A Lepidopteron feeding on scale insects. — May 7, a Lecanium scale 

 insect was observed on the twigs of scrub pine in Hampshire County, 

 and a lepidopterous larva was found feeding upon the scales, after 



