INJURIOUS INSECTS. 



309 



should then be somewhat uucovered and copiously drenched with very 

 hot, but not quite boiling water, or with strong soap-suds. An applica- 

 tion of soap-suds with about one pint of turpentine to a gallon of suds 

 has also been recommended. Kerosene emulsion is also a reliable 

 remedy when thoroughly applied, and that vile-smelling and inflamable 

 chemical, bi sulphide of carbon, may also be used effectively by pour- 

 ing a few tablespoonfuls into holes made around the tree which should 

 be covered as soon as the sulphide has been injected. 



The woolly aphis on the trunk and branches can be cleared off, 

 with comparative ease, by one or two drenchings with kerosene 

 emulsion. 



THE PEACH-TREE BARK-LOUSE. 



(Lecanium persicce, Modeer). 



The peach-tree scale is a recent addition to the injurious insect 

 fauna of Missouri. Previous to my observations upon it, published in 

 Bulletin 32 (1894) of the U. S. Department of Agriculture, there is no 

 record of its presence in any part of the State. It was first brought 

 to my notice during the meeting of the Horticultural Society at Car- 



Fig. 3. The Peach-tree bark-louse (Lecanium persicrp). Newly hatched 

 on the right; yoan? female next; twig wlth'full grown female scales; female 

 scales from above and underneath— all much enlarged except specimens on 

 twig. From Department of Agriculture. 



thage, when the janitor of the hall exhibited several branches badly 

 infested with it. Strangely enough, the following spring I received a 

 number of letters from different parts of the State complaining of its 

 prevalence, and about the same time a neighbor brought me some 

 twigs covered with a "new pest" that caused him much apprehension. 

 This gave me the much desired opportunity to study the habits and 

 development of the species, to which I accordingly devoted considera- 

 ble time during the summer of 1894. This seemed the more worth 



