65 



though at a later visit, on June 14, nearly all were dead, the living 

 specimens being without exception on the side of the tree opposite from 

 the sun. The alternating extremes of temperature or some other cause 

 had so reduced the number of adult females that comparatively few 

 young had been developed. If similar conditions have existed since 

 the tree was planted in the spring of 1894, it is not difficult to under- 

 stand why it has not succumbed to the attack of the insect. 



While these observations show conclusively that this scale can suc- 

 cessfully exist in Massachusetts in spite of the rigors of* our New 

 England climate, it seems doubtful if the insect will prove a serious 

 pest in this region. 



These specimens of Diaspis amygdali, together with others received 

 from various sources, were compared with specimens of Ghionaspis 

 prunicola received from Professor Maskell, the author of the species, 

 and found to be identical. The writer therefore considers Ohionaspis 

 prunicola to be a synonym of Diaspis amygdali, since the latter specific 

 name has priority. 



In the discussion, Mr. Smith, referring to the notes on Pseudococcus, 

 said the experience cited was interesting from its contradictory nature, 

 but he questioned if the explanation of the disappearance of the insect 

 in some instances was due to the treatment. He was of the opinion, 

 on the contrary, that it might be from an entirely different cause. He 

 illustrated his ground for this belief by his experience with this insect 

 in New Jersey, where it had disappeared without apparent cause after 

 having increased steadily for three years. He referred to the possibility 

 of clearing them from the surface of the bark by the application of a 

 strong stream of water from a watering hose. 



Mr. Alwood expressed considerable interest in the report of excessive 

 injury from the presence of Aspidiotus ancylus, and particularly in the 

 fact that a tree had been killed by this insect. He stated that he knew 

 of a tree covered with this scale in Virginia, and that fatal results had 

 not followed. He said that it was a difficult species to determine on 

 account of its variability. He had never known it to be sufficiently 

 numerous to destroy trees, referring particularly to its occurrence on 

 apple. He stated that he had often received A. forbesi from Georgia, 

 where it was very destructive. 



Mr. Johusou remarked that he had also had forbesi from Georgia, 

 receiving it from Mr. Scott. In Illinois he had found this species two 

 brooded, but the specimens received from Georgia indicated a possibility 

 of four full broods in that State. This species, which he said was often 

 mistaken for per niciosus, had been received by him from Mr. Fletcher 

 in Canada and from Mr. Oockerell in New Mexico, and it also occurs in 

 Maryland. It is a very common species on apple, and can always be 

 recognized by the pitted appearance of the bark of an infested twig, 

 7184— No. 17 5 



