222 Miss A. L. Embleton on the 



evidence that such is the case. This ignorance is often 

 responsible for much harm that is done in the way of apply- 

 ing so-called remedies to exterminate the scale or mealy- 

 bug ; for, when the creature is already destroyed by the 

 parasite, it is not only superfluous but highly injurious to 

 apply insecticides or similar remedies, for these arc then 

 really destroying the beneficial insects which keep the 

 scale in check. 



Attention has lately been called to this important point * 

 in the report of a discussion on the subject in America. 

 Mr. Johnson "said that he had bred Aphclinusfuscipennis 

 in crreat abundance from the San Jose scale this autumn. 



® . . . 



He is inclined to think that this parasite has become so 

 abundant that it will be necessary to alter remedial mea- 

 sures against the scale. Instead of cutting down and burn- 

 ing at once, he will recommend girdling the trees and 

 killing them, and then leaving them until all parasites 

 have had a chance to escape before they are burned. He 

 stated that he even doubts the wisdom of winter spraying, 

 although he is not certain as to the stage in which the 

 parasite hibernates." This discussion finally took the form 

 of considering in what state these parasites of scales 

 hibernate. 



My own observations induce me to emphasize the im- 

 portance of the remarks quoted above. As regards hiberna- 

 tion I can say that the parasite oiLecanmmhemispliiBncuiii 

 var. filicum passes the winter in quite a variety of stages. 

 Specimens of the perfect insect were observed in the act of 

 emerging early lost autumn, and they have continued to 

 do so during the winter, except that emergence was inter- 

 rupted by the very cold weather. During the winter I have 

 examined and mounted a large number of the Lccanium 

 and its parasite, and I have found all stages of the latter 

 from half-grown larvae to pupse as well as adults ready for 

 emergence, and waiting apparently only for a favourable 

 moment. All the specimens that emerged in the autumn 

 and Avinter were females, but in the last few days (^larch) 

 the other sex has begun to appear. This Lccanium I have 

 studied chicfiy on ferns, but it occurs on other plants. King f 

 says of this species : "Zecanium hemisphcvricum Targioni 

 Tozzetti, 1869. This is one of the commonest of scale insects 

 found in greenhouses and on potted plants in dwelling- 



* P. Ent. Soc, Wasliington, iv, part 4, July 1901, p. 413. 

 ■\ "Greenhouse Coccklx." Ent. News, Philad., xii, p. 311. 



