16 FIRST ANNUAL REPORT OP 



F. Starr, of Alton, Illinois, covered with a species, which, if not the 

 same, is exceedingly like it. 



Natural Remedies. — It was last year simultaneously discovered 

 by Mr. Walsh and Mr. Shinier, that a species of mite ( Acarus family) 

 preyed unmercifully on the louse as well as on its eggs. This mite 

 was described by Mr. Shinier as Acarus mains in the paper already 

 referred to, and it appears that it greatly resembles the young bark- 

 lice. Mites are not true insects, but belong to the same class ( Araeh- 

 nida) to which our spiders belong, and although the species are nu- 

 merous — some causing galls on plants, some living externally on 

 vegetable substances and seeds, either in a sound or rotten condition, 

 others devouring animal substances, both dead and living, while 

 others again are parasitic on certain animals — yet they all are readily* 

 distinguished in the perfect state from true insects by having four 

 pairs of legs, and by the head and thorax being soldered in one piece 

 without any joint whatever. Some of them, in the larval state, have 

 but six legs, thus still more closely mimicking the young bark-lice, 

 but they all acquire eight in the full grown state. This mite, so insig- 

 nificant that in the larval state it can only be noticed by careful 

 watching with a pocket-lens, has, doubtless, done more to save the 

 apple trees in the Northern States than anyone thing else; and its 

 existence explains the gradual decrease of the Bark-louse that is 

 known to have occurred in many orchards, and also accounts for its 

 entire extermination on certain trees. 



Fig. 4. The next most efficient aid we have is the Twice-stabbed 



PWh£/' lady-bird ( CMlocorus bivulnerus, Muls.) This good friend 

 j§^^k^ I is readily recognized by its polished black color, and the 

 aMSlF* blood-red spotoneach wing-case. Itis represented magni- 

 r^JB^V fled at Figure 4, the hair line at the side showing the natural 

 length. Its larva (Fig. 5) is a dark gray prickly affair, and is extreme- 

 Fig. 5. ly active and voracious. In changing to pupa, the 

 larval skin splits open on the back, but the naked 

 ifea pupa, which is of the color of burnt-umber with lighter 

 sides, remains within it as if for protection. In this latfer 

 state these lady-birds may often be found fastened in clusters of from 

 six to twenty on apple trees affected with either kind of bark-louse, 

 and they should invariably be protected. It is astonishing how rapid- 

 ly they will cleanse a tree from its vermin, and there is no better way. 

 of getting rid of bark-lice than by introducing a few of these little 

 friends onto the lousy tree. 



Artificial Remedies. — These may be summed up in a very few 

 words, and consist, for the most part, in prevention, and I again urge 

 a strict examination of every young tree before it is planted. If an 

 orchard is once attacked before its owner is aware of it, much could 

 be done on young tress by scraping the scales off in winter, but on 

 large trees where it is difficult to reach all the terminal twigs, this 

 method becomes altogether impracticable, and it will avail but little 



