2S4 EDITOR'S TABLE. 



"Wliother those ineocta bnvc any connexion or concern with the production of the warts on the 

 cherrv nml on the jiluni tree, is a question of considerable importance. Your friend Georgb 

 Clarkk, l>q., who furnished you -with the epeciincns eent to nic, has satiiificd himself, you say, 

 tiiat the warts originate from the punctures of these insects. Having watched the operations of 

 the latter for three years past, he has found the warts to appear on the wounded twign ; and has 

 found, "also, that, when the wounded part was cut ont, the production of warts was prevented. 

 Since the receipt of your specimens, I have examined (not very thoroughly indeed) my plum 

 trees which have always had some warts on them every summer ; but I do not discover any 

 incision of the Mcmbracis upon the twigs. This examination, however, is not to be considered as 

 a sufficiout or satisfactory test. My trees have been very severely pruned and shortened on the 

 first appearance of the warts, and in this way have been kept free from the unsightly excrescences 

 with which other trees are disfigured. I can detect the wart in its incij)ient stage, bef&re even 

 the delicate outer skin of the twig is broken by the tumid condition of the bark, and then apply 

 the knife freely, and put fine salt or strong brine upon the wound. I propose this spring to wash 

 over all the limbs and twigs of my plum trees with strong soft soap, in order to ascertain whether 

 alkali will prevent the production of the wart — be their cause what it may. Before this is done, 

 however, I will examine the trees again more careful]}-, and if any incisions of the Mcmhracia 

 are found, will mark the spot by tying around it loosely a piece of yarn — will then leave it 

 untouched by the soap, and watch the result. I hope other persons may be induced to make tho 

 same experiment. 



I should observe that Memhracis bubalus is not an uncommon insect here, and that it may be 

 found by a careful collector almost every summer. Yours, etc., Thaddeus Wm. Hakeis. 



Cambridge, Mass., March 28, 1S53. 



P. S. — You will find by my Treatise, page 70, that the black color of the surface of the warts 

 on the plum tree is occasioned by numerous little black spherical fungi, which give to the wart a 

 gr.anulatcd appearance. The constant occurrence of these fungi on the surface of the warto, and 

 upon nothing else, and the invariable death of the warts when the fungi have come to maturity 

 and have shed their spores (or seeds), are of much significance in connection with the origin and 

 history of this peculiar affection. T. W. H. 



"We are greatly obliged to CoL JonxsoN for the information he lias communicatecl. 

 Whether or no the " Menibracis''' produces the plum tree -warts, it is well that attention 

 should be called to it, that the precise nature of its depredations be understood. 



The three great draw backs in fruit culture in America are the ^^ear Might, the cutcuUo 

 and the Plu/ii tree hearts. Tliose subjects merit thorough and ceaseless experiment and 



investigation. 



♦ 



Notes bt a MicniCAN Correspondent. — I notice your Baldwinsville correspondent's inquiry 

 regarding cocoons on the apple tree. I have frequently detected them in my orchard here, but 

 had not detected the moth. So far as I can ascertain, they are, in common with at least two 

 other apple tree insects which abound here, perfectly harmless. One of these is a minute black- 

 winged fl}-, not unlike a very small wasp or female ant, which lays clusters of shining black eggs 

 — two to three dozen together — under the loose bark. The eggs are exceedingly abundant, but 

 the fly appears to be scarce. In its winged condition, it probably has another habitat, but I have 

 detected it laying its eggs in the fall. These latter, under a good microscope, are very beautiful, 

 being of the deepest black with the very highest polish. Does it exist with you? If it does, 

 you cannot fail, when cleaning your trees in the spring, to have seen the eggs. 



There is another insect, of whose harmlessness I am not so confident. I believe it to be an 

 aphh, but have never met with any description of it. It is a clumsy, soft, bed-bug-looking crea 

 ture, about the size of this familiar pest, of a dark greyish-green, regularly striated across the 



