SCALE INSECTS OF IMPORTANCE 



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Distribution. This insect is well distributed over New York state 

 and is present in many other states, as shown by the following compiled 

 list : Massachusetts, Rhode Island, Connecticut, New York, New Jersey, 

 Delaware, Pennsylvania, Maryland, Virginia, West Virginia, District of 

 Columbia, Kentucky, Tennessee, Georgia, Kansas, Mississippi, Ohio, 

 Indiana, Illinois, Missouri, Iowa, Nebraska, Utah, South Dakota and 

 California. It has also been recorded from Ontario, Nova Scotia, New 

 Brunswick and Prince Edward Island. The absence of record by no 

 means implies that the scale is not known in the omitted states. It has 

 also been recorded from England, having been carried there on R i b e s 

 sanguineum. Dr Howard, in his account of this insect, alludes to 



Fig, 3. Ablerus cllsiocam pae, female greatly enlarged. (After Howard. lusect life. 1S94. 7:7) 



an early record where it is stated that the appletree bark louse is gradu- 

 ally supplanting this pest, and proceeds to state that the former is appar- 

 ently the hardier, and that he believes that it will in time take the place 

 of Chionaspis fur fur a. Both species have been in New York 

 state for about 50 years at least, and it does not appear that the native 

 form has been materially checked by the presence of a more hardy rival. 

 Natural enemies. One hymenopterous parasite, Ablerus clis- 

 iocampae Ashm., has been bred from this scale insect by Dr How- 

 ard. Two Coccinellids, H y p e r a s p i d i u s species and C h i 1 o c - 

 orus bivulnerus Muls., the twice stabbed lady bug, prey on this 

 pest. The latter is stated to be a specially valuable enemy. 



