108 STATE HORTICULTURAL SOCIETY. 



at the close, it lies almost against the abdomen. At the beginning of the opera- 

 tion the body is raised on its limbs and sways from side to side, but as the cutting 

 continues backward the vibratory motion ceases somewhat and the abdomen is 

 lowered, till on the completion of the slit it rests on the twig. The insertion of 

 the eggs immediately follows. Beginning at the end of the slit last made, the 

 ovipositor is thrust down through the bark, reaching the cambium layer— the 

 abdomen of the insect resting on the limb, inclined in the direction of the oviposi- 

 tor. At intervals of from one-half to two minutes, the ovipositor is drawn forci- 

 bly forward and sometimes partly out of the slit, and then reinserted. By noting 

 the number of times this movement was repeated, it was found to agree with the 

 number of eggs in the slit. The making and filling of the first slit requires from 

 20 to 25 minutes, after which the ovipositor is entirely withdrawn, and a second 

 slit, shorter than the first, parallel to and curving toward it, is made without 

 change of position by the insect. The insertion of the ovipositor and introduc- 

 tion of the eggs in the second slit are as described for the first, after which a rest 

 of considerable length is taken before the insect again begins work. The eggs 

 are whitish, slightly curved, each 1-16 of an inch long, arranged in two parallel 

 rows of from six to ten each, separated by a narrow strip of bark." 



The above circumstantial account will enable the oichaidist to 

 understand how and for what purpose the cuts are made. Tbe insects 

 are somewhat gregarious, and the work of one often follows on the 

 same branch that of another. In the case of the work of the insect, 

 as observed in Oregon, Mr Luckhardt's orchard was the only one out 

 of hundreds in that section upon which it was seriously iojurious, and 

 Mr. Marlatt made the same observation of the orchard near Manhat- 

 tan, where his studies of the insect were pursued. 



During April and May of 1893, I received many letters of inquiry 

 concerning the scarred twigs on which Ceresa had oviposited, includ- 

 ing some from our honored secretary, Mr. Goodman, Mr. Gilbert of 

 Thayer, Mr. Gilkeson of Warrensburg, Mr. Groflf of Iberia, who writes 

 " There is something working in my orchard and I send you a piece of 

 limb affected. The trees are three years old and are stung all over. 

 Can you tell me what it is and give me a remedy for the same?" Mr. 

 Gilkeson says in regard to the specimens sent: "They are from the 

 orchard of Dr. S. P. Cutter, and he has 2000 trees that are affected in the 

 same way." These letters show that the insect has really become, in 

 some orchards, a most formidable enemy, requiring energetic fighting. 

 I have not been able to obtain evidence substantiating Mr. Marlatt's 

 suggestion that the insect preferred one variety of apple over another 

 in placing its eggs. In orchards such as those mentioned in the above 

 extracts, it is more than probable that several varieties were included. 



Mr. Goodman, of all my correspondents, alone named the variety 

 of tree, the Willow Twig, from which the injured twigs were taken. 



The only preventive measure that seems practicable is severe 

 pruning and burning of the affected twigs during winter and early 



