FAMILY AI'HIDID.t. 161 



A species of Tiirips infests the kernel of wheat while in its milk state ; and it is quite 

 doubtful whether this one ean he destroyed by the a;>|ilication of tine slaked lime, as has 

 been reeoinmended : still, when the dew is on the ]'l;int, a free si>iinkling may be tried, 

 which, if not Mioeessful in the way desiirned, will at lea>t benefit the soil. 



The disease called npp/(7/T<' W(>^/ is due to another eenus of aphides, the Ehiosoma. 

 It is a woolly insect, destitute ufwiii'.'s, I'Ut is wafted firm tree to tree by the buoyancy of 

 its woolly envelop!-. The ecgs, only visible under a niicrosco])e,are tnvelojicd in a cotton- 

 like substance fouuil in crotches of the tree and chinks of the bark ; and if there are 

 suckers standing around the tree, it may be fountl on them also. The fnll-grown insect is 

 one-tenth of an inch long, emits a sticky juice from its extremity, and is covered with 

 Hakes of down : when this is removed, the color of the antennrp, head, sucker, and spines 

 is blackish ; abdomen honey-yellow ( Haruis). It feeds upon the sap of the alburnum of 

 the apple-tree ; and the wounds it inflicts give origin to warts, excrescences, and inequali- 

 ties upon the bark : the liual result of its attack is the death of the tree. 



It ajipears from the accounts which have been published of the ravages of this ajihis in 

 England and in this country, that the only hope of arresting the evil lies in beginning at 

 once, or as sotm as the insect makes its appearance. After it has extended itself far and 

 wide upon the large trees of an orchard, it becomes exceedingly difficult to arrest its 

 progress, and this probably only hai)pens in cases when the weather becomes unfavorable 

 to the life and propagation of the insect. The rational way to go to work, will be to scrape 

 thoroughly all the trunks and larger limbs, and then to scrub the suil'ace with strong 

 soapsuils, or whitewash them. When the trunk beneath the soil and the roots are infested, 

 extend the treatment to these parts also. Mr. Harris recommends a solution of potash, 

 and to protect all the wounded parts by grafting wax, and also the removal of all refuse 

 from and about the tree that may contain the eggs or the living animals : cut off, like- 

 wise, and burn all the smaller limbs. It seems that all strongly scented solutions, such as 

 tobacco water, ammonia, etc. are more or less effectual remedies against the depredations 

 of the various kinds of ajihidcs. 



Another interesting and important lact in natural history is that jilant-lice have nume- 

 rous foes, that jirey upon and destroy them in great nund)ers : among these foes we may 

 rank the numerous species of Coccinella, or ladybirds (See Plate xi, where several of the 

 most common kinds are figured). A person unacquainted with these small and beautiful 

 insects, on seeing them upon an infected plant, might mistake their characters and office, 

 and attribute to their presence the sickly state of the plant. He could not well commit a 

 greater mistake ; and to convince himself of this, he would only need to watch tlie move- 

 ments of the little beetle for a short time, when he would find that its errand was one of 

 kindness to him and his plant, for he would soon observe it feeding ujn'ii the jilant-lice : 

 these constitute its food, both in the larva and mature states, so that its services in re- 

 [ Agricultural Report — Vol. v.] 21 



