io6 INSECTS 



sumed the dimensions of a calamity and, as one excited 

 grower informed me, even the hitching posts became 

 infested. The introduction of the ladybird enemy 

 which had been discovered in the native home of the 

 scale turned the tables at once. In less time than it 

 had taken the scale to overrun the country, the Vedalia 

 aided by artificial breedings and distribution, cleaned 

 it out, until now both scale and beetle barely maintain 

 themselves. There are undoubtedly many other similar 

 relations, but on this point we have yet much to learn. 

 It rarely happens that a Coccinellid beetle ranges 

 far from its normal food or a very closely allied species, 

 and- however flexible and adaptable it may be in rela- 

 tion to its normal prey, it generally fails when pitted 

 against an unknown or new form. The San Jose or 

 pernicious scale is a rather close ally of several of our 

 native armored scales, and the Coccinellids that feed 

 upon these also attack this introduced form; but east 

 of the Rocky Mountains none of them exercise the 

 least real control over it. On the Pacific Coast the 

 Chilocorus bivulnerus or twice-stabbed ladybird does 

 act as an effective check because, having several broods 

 during the season, it becomes plentiful enough to de- 

 vour a large percentage of the hibernating forms. In 

 the east this same species has only a single brood and 

 is absolutely impotent. And when we brought in the 

 closely allied Asiatic Chilocorus similis to help us out, 

 that flourished for a year or two in one of our southern 

 states and then died off. In the more northern states 

 it never gained a foothold at all. The little Smilia 

 misella, native to the Atlantic states, becomes plenti- 

 ful enough at times, and may be found feeding even in 

 midwinter; but while it undoubtedly helps to keep 

 down numbers somewhat, it cannot be considered an 

 effective enemy. 



