328 BOARD OF AGRICrLTURE. [Pub. Doc. 



served by many citizens, and many specimens have been found on the 

 sidewalks in the suburbs of Boston, where they had been stepped upon by 

 pedestrians. 



The European Tachinid fly, Coinpsllura concinnata, was also very 

 abundant this year, and did excellent work in the vicinity of Boston. 

 From a collection of about 12,000 caterpillars made in Stoneham, Saugus 

 and Melrose, Mass., it was found that over 25 per cent, were parasitized 

 by this insect. 



An unlooked-for development occurred during the summer when small 

 gypsy moth caterpillars were found to have been parasitized by Apanteles 

 ladeicolor, another introduced parasite. Previously, only a single cocoon 

 had been collected, in the summer of 1911. During the summer of 1912 

 the parasitism of gypsy moth caterpillars by this insect has been found 

 over a wide area, from as far north as Manchester, N. H., to Hudson, 

 Marlborough, and towns in this vicinity in Massachusetts, and also in 

 towns around Boston. On account of the difficulty of observing this 

 species, it is probably safe to say that a large amount of beneficial work 

 performed by it has escaped notice. 



Some of the other parasites, such as the Tachinid, Blepharipa, are in- 

 creasing, as has been demonstrated by the work done during the past year. 



In several places in the area which was badly infested during past years, 

 it is a fair estimate that 50 per cent, or more of the gypsy moth larv®, 

 pupae and eggs were destroyed during the sunmier of 1911 by the parasites 

 above mentioned. In other areas, farther from the centers of parasite 

 plantings, of course, so good a showing was not made. 



It should be stated that the wilt disease was present during the season 

 of 1912 as heretofore. It was almost impossible to find an infested area 

 where the disease was not present some time during the caterpillar season. 



The present condition of the brown-tail moth indicates a greater measure 

 of control by introduced parasites than ever before. During the spring 

 of 1912 climatic conditions were such that the fungous disease which 

 attacks this insect in early June did not develop to any marked extent 

 in the region about Boston. The previous winter was very severe, and 

 many collections of brown-tail nests were made to determine the number 

 of caterpillars which died in the webs during the winter from cold weather 

 or other causes. The records from Maine, New Hampshire and the 

 western part of the infested area in Massachusetts showed that a far larger 

 percentage of dead caterpillars were found in the webs than in the districts 

 surrounding Boston. This being the case, one would naturally expect a 

 large increase in the brown^tail moth infestation about Boston this autumn. 

 The condition of infestation, however, is not nearly so great as would be 

 expected, and, as the fungous disease worked to a very slight extent in 

 this particular region, it is reasonably obvious that the parasites were 

 largely responsible for the present decrease. Collections and recoveries 

 from the field also showed that the species which were most abundant in 

 this region last year were far more common in 1912. Apanteles ladeicolor, 



