162 FIRST ANNUAL REPORT OF THE STATE ENTOMOLOGIST. 



Greenland, may often be found in books and in insect cases ; it has 

 been discovered in the Mammoth Cave, Kentucky, upon animal re- 

 mains. * Clothilla pulsatoria (Linn.), known in England as the " death- 

 watch," from the ticking sound made by it, and Psocus domeslicus 

 Burm., also infest collections of natural history. In Hagen's JVeurop- 

 tera of North America, of the sixteen species of Psocus described, 

 nine are credited to the State of New York. Later studies have changed 

 the generic references of several of these, and other species of Psoci 

 occurring in New York have since been described. 



Remedies. 



When the apple-leaf Bucculatrix occurs abundantly upon young 

 trees, if the trees are given a sudden jar, when the caterpillars have 

 about attained their growth, at some time during the months of May 

 and September, large numbers of the caterpillars which drop froin 

 the leaves and hang suspended by their silken threads can be 

 swept upon a broom and crushed, or scalded in hot water. The appli- 

 cation of kerosene oil, diluted with hot soap-suds, to the cocoons, by 

 means of a force-pump and spray-machine or atomizer, has been recom- 

 mended. If applied during the month of March or April, when the 

 circulation of the sap has commenced, the chance of injury to the 

 tree will be less. Linseed oil might also be employed, but would not 

 so readily penetrate the cocoons to the inclosed pupge, which must be 

 reached in order to prove effectual. 



If the limited number of the cocoons admit of their removal by 

 scraping them from the twigs, this would be the better method to 

 employ. Their white color at once discloses their presence, and serves 

 to show when their complete removal has been effected. 



Mr. Chambers, in a late communication to the American Ento- 

 mologist {loc, cit.), expresses his belief that the destruction of the 

 pupae within their cocoons upon infested apple-trees, by spraying them 

 with oil, may not place the insect within our control, for the follow- 

 ing reason : He had found as many as twenty of its cocoons in a clus- 

 ter on elder [Samhucus), at least fifty yards distant from the nearest 

 apple-tree, and there were no indications, or was it probable, that the 

 larvse ever fed upon the leaves of the elder. The species, therefore, 

 shared the habit not uncommon in Bucculatrix larvae of deserting their 

 natural food-plant wlien mature, and wandering elsewhere to spin their 

 cocoons. Mr. Chambers suspects that Bucculatrix thuiella, found by 

 Dr. Packard on Tlmja^ may only have wandered thither from some 

 other food-plant, as it was not observed as depredating on the cedar. f 



*Hubbard : in American Entomologist, iii, 1880, p. 89. 



^American Katurallst, v, p. 149; American Entomologist, iii, 1880, p. 50. 



