694 



Bulletin 83. 



be seen on one of the branches in the figure on the title page. A close 

 examination showed that these scales contained parasites ; which 

 we did notsucceed in breeding. The parasite is probably a minute 

 four-winged hymenopterous fly which lays her eggs in the young 

 scales, perhaps in the fall. The percentage of the scales thus 

 destroyed this year was not great, but this little foe may become 

 a valuable ally in checking this pest in the near future. 



In figure 4 is shown the 

 spiny larval skins, many of 

 them containing pupae, of 

 the twice-stabbed lyady-bird 

 beetle {Chilocorus bivulne- 

 rus) which is very common 

 in some infested plum or- 

 chards. We have seen hun- 

 dreds of the spiny skins in 

 groups about the trees, but 

 have not observed the Lady- 

 bird at work on the scales. 

 One of the beetles is just 

 emerging from one of the pu- 

 pae in the figure. It is a 

 small beetle, about as large 

 as and shaped somewhat like 

 one of the shells of the Plum 

 Scale. But it is of a shining 

 black color and has a bright 

 red spot on each wing cover. 

 This Lady-bird is very com- 

 mon throughout the country, and is said to be the most effective 

 enemy of scale insects in Florida. Both the beetles and their 

 spiny larvse feed upon the scales. Protect these little friends. 



There are doubtless other Lady-bird beetles that are predaceous 

 on this plum scale, and perhaps other true parasites are at work 

 upon it. But the balance of nature seems to have tipped decid- 

 edly in favor of the scale at present in western New York, yet 

 these little foes will materially aid in restoring the equilibrium in 

 the future. 



Fig. 4. — Spiny larval skins of Lady- 

 bird Beetles ; and many young phini 

 scales in hibernation. Natural size. 



