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I consider the cherry scale the most dangerous scale insect now 

 established in Illinois. It has a variety of food plants, but wild and 

 cultivated cherry seem to be its favorite. I have found it also on apple, 

 pear, plum, quince, currant, and possibly honey locnst and mountain ash. 

 It attacks the trunk and branches and is occasionally found on the 

 leaves and fruit. In June of the present year I found several imma- 

 ture scales on cherries. July 6, 1895, I collected several currants on 

 which scales of this species were found, and August 14, 1895, 1 gath- 

 ered apples from the Illinois Experiment Station farm containing 

 scales of fully matured females. 



It hibernates as a partially matured insect and is double brooded in 

 the latitude of Springfield, 111. The mature males begin to appear 

 about the middle of April and the first brood makes its appearance 

 early in May. It is not an uncommon thing, however, to find young 

 and eggs as late as June 20. The mature males of the second brood 

 begin to appear about July 10 and continue to emerge until about 

 the first of August. I am of the opinion that there are three broods in 

 extreme southern Illinois. It is related to Putnam's Aspidiotus ancylus, 

 but may be readily distinguished from that species by the second pair 

 of lobes of the last segment of the female, the number of spinnerets 

 and other characters presented by the adult male, and the scales of 

 both sexes. 



This pest, however, is by no means free from the attacks of natural 

 enemies. I have reared from it seven species of hymenopterous par- 

 asites, determined for me by Dr. L. O. Howard, as follows: Prospalta 

 murtfeldti How., Prospalta aurantii How., Perrisopterus pulchellus How., 

 Signiphora nigrita Howard MS., Arrhenophagits chionaspidis Aur., Able- 

 rus clisiocampte Ashrn., and a species belonging to the genus Encyrtus. 

 The twice-stabbed ladybird (Chilocomis Mvulnerus) and its larva are very 

 important factors in the reduction of this scale insect. I have very 

 often found a small whitish mite under scales containing dead male 

 pupae. Whether the pupa had been killed by the mites or whether they 

 had been attracted there by the presence of the dead insect I have not 

 been able to determine as yet. 



In spite of its natural enemies it has a firm foothold in Illinois, and 

 can be kept in check only by the most energetic and persistent fighting. 

 It is not an uncommon thing to find 7 and 8 year old cherry trees in that 

 State literally covered with this destructive scale. It is also present in 

 certain nurseries in Illinois, as I know from personal inspection. It is 

 of great consequence, therefore, to all those interested in fruit culture 

 to be on the lookout for this ravenous pest. 



I Avish to call your attention to three other species of Aspidiotus 

 recently described by myself. Only one of these, however, is of much 

 consequence from the economic standpoint. I have proposed to call it 

 Aspidiotus eomstocki in honor of my teacher and friend, Prof. Ji II. 

 Comstock, of Cornell University. It has been very abundant for several 

 years on sugar maple (Acer saccharinum) in Illinois, at .Mount Carmel, 



