ENTOMOLOGISTS REPORT. 107 



not be ehowu. The popular name is derived from the projecting horns 

 on the prothorax. 



The first orchard suffering seriously from its attacks, that came 

 under my observation, was that of Mr. G. F. Luckhardt, of Oregon, 

 Mo. At the summer meeting of the State Horticultural Society in that 

 city in 1888, specimen twigs and branches were exhibited showing ex- 

 ceedingly disastrous work. The branches were cut and scarred almost 

 continuously^ from base to tip, both two and three-year-old wood being 

 involved, and the scanty foliage that had put forth was yellowed and 

 wilted from the effects of innumerable punctures in the petioles and 

 principal veins by the young larvjB. 



The latter do not in any particular, except in beak 

 and legs, resemble the mature insect. Dr. Riley de- 

 scribes them as "at first brownish, with a formidable 

 row of ten pairs of compound spines. After the first 

 and second molts they are still furnished with these 

 sprangling spines, but are of a paler color, with some 

 «-®' transverse, lilac-colored lines. With the third molt 

 ^offarvffiT^^'jXTrc, they assume the pupa state, in which the wing-pads 

 "arg^d^raiter Riley", become conspicuous and the prothorax is produced 

 into a point behind. With the fourth molt, which takes place toward 

 the end of July, the characteristics of the mature insect are acquired." 

 The above description of the immature forms was published by Dr. 

 Riley in 1873, in his fifth report on the Insects of Missouri, but to Mr. 

 C. L. Marlatt, at present of the TJ. S. Division of Entomology, but 

 formerly of Kansas, belongs the honor of having first observed and 

 described the processes of oviposition, which he also correctly deline- 

 ated in Fig. 1. The account was published in the Kansas Academy of 

 Science, Vol. X, for the loan of a copy of which, as also of the illus- 

 tration pertaining to it, I am indebted to the kindness of Prof. E. A. 

 Popenoe, of Manhattan. 



Oviposition takes place through the months of September and 

 October, and the mode of procedure is described by Mr. Marlatt as 

 follows : 



"The female chooses by preference a twig of two or three years' growth, 

 not. however, confining its work to twigs of this age. Eggs are deposited quite as 

 readily in the new growth of old as well as young trees, and my observations would 

 lead me to believe that certain varieties, owing to differences in the texture of the 

 bark, are more liable to be attacked than others. During oviposition the female 

 may head away from or toward the trunk. ( Fig. 1, d. c.) A slightly curved slit 

 through the outer bark is started with the ovipositor at right angles to the body, 

 and the cutis made from the point of insertion posteriorly, the ovipositor con- 

 stantly assuming a more and more slanting position as the cutting proceeds, till, 



