124 MISSOURI STATF HORTICULTURAL SOCIETY. 



they were subjected. Perhaps he will be k'ind enou<,rh to give us the 

 particulars as a supplement to this report. 



There is nothing very recent concerning this insect in entomological 

 literature. The most complete account that we have of its habits was 

 published in the first volume of the American Entomologist, page 8i, 

 prepared, I think, by Mr. B, D. Walsh, the senior editor and first State 

 Entomologist of IllinoiF. 



Drs. Fitch and Harris had previously described the aerial form which 

 inhabits the trunk and branches of the tree, but they were unacquainted 

 with the root feeding form or considered it a distinct species. Mr. Walsh 

 himself entertained the latter opinion, but in this none of the later auth- 

 ors agree with him. 



In his third Missouri report, speaking incidentally of this insect, 

 Prof. Riley says : "It is conceded on almost all sides that the insect 

 was imported into Europe from this country, and there is now every 

 reason for believing the two insects (the Wooly bark louse and Wooly 

 root louse) identical, or at furthest they can only be considered as 

 varieties of one species. Yet, while in this country our root louse is 

 very injurious in the west, and only exceptionally found on the limbs 

 above ground, (though more often so found in the eastern states,) all 

 authors that we are acquainted with have spoken of it as occurring solely 

 on the limbs in Europe; though Mr. Lichtenstein informs us that he has 

 found it on the roots also, and that it caused in those cases, just such 

 swellings of the roots as our root louse does here. 



The experience of the proprietors of the Oldtn Fruit P'arms, has 

 proved, I think, that sandy and gravelly soils are particularly favorable 

 for the development of this ins' ct on the roots of young trees. It cer- 

 tainly does not make much headway in stiff soils and I have also ob- 

 served that it is often quite abundant on the trunks and branches of trees 

 during wet seasons, and at such times the roots would be almost or en- 

 tirely free from its presence. 



The wingless lice arc of a pale yellow color, with darker heads, legs 

 and antennae, and have the hinder part of the body enveloped in a mass 

 of bluish white, cottony matter which is often secreted, especially on the 

 roots, in such vast quantities as to completely fill the soil. They have 

 no honey tubes, but a sweet sticky fluid is often mingled with the 

 cottony secretions. The beak is long and fine and the effects of its 

 punctures is seen in the nodulose swellings and knots in which the vege- 

 table tissue becomes perverted and hardened, thus interrupting circu- 

 lation and causing decay. On the trunk the insects cluster about the 



