$G TIIlRti ANNUAL REPORT OP 



which he would soon have to give. They act, indeed, as Nature's 

 priming-knives. But the late and severe frost which killed the first 

 buds last April, so retarded the growth of the vines that the worms 

 were out in force before the third bunch had fully formed, and 

 this bunch was consequently included in the fold made by these 

 worms, and destroyed. 



The larva of the Grape-vine Plume invariably hatches soon after 

 the leaves begin to expand; and thong!) it is very generally called 

 the Leaf folder, it must not be confounded with the true Leaf-folder, 

 which was just now described, and which does its principal damage 

 later in the season. At first the larva of our Plume is smooth and 

 .almost destitute of hairs, but after each moult the hairs become more 

 perceptible, and when full grown the larva appears as at Figure 27, e, 

 the hairs arising from a transverse row of warts, each joint having 

 four above and six below the breathing-pores * (see Fig. 27, e). After 

 feeding for about three weeks, our little worm fastens itself securely 

 by the hind legs to the underside of some leaf or other object, and, 

 •casting its hairy skin, transforms to the pupa state. This pupa (Fig. 

 27, 5), with the lower part of the three or four terminal joints attached 

 to a little silk previously spun by the worm, hangs at aslant of about 

 40°. It is of peculiar and characteristic form, being ridged and angu- 

 lar, with numerous projections, and having remnants of the larval 

 warts; it is obliquely truncated at the head, but is chiefly distin- 

 guished by two compressed sharp-pointed horns, one of which is en- 

 larged at Figure 27, <?, projecting from the middle of the back; it 

 measures, on an average, rather more than one-third inch, and varies 

 in color from light green with darker green shadings, to pale straw- 

 color with light brown shadings. 



The philosophic student of insect life cannot fail to be struck 

 with the wonderful disguises which these little animals often assume, 

 the better to escape detection from their enemies. The instances of 

 protective mimicry are more numerous among insects than among 

 any other Class of animals, and in the last part of this Report, I shall 

 have occasion to refer to this subject more fully. I had often won- 

 dered why the pupa of the Grape-vine Plume was seldom noticed in 

 the open vineyard, and I very well recollect, when three years ago, 

 this worm was abundant in the vineyard of the Rev. Charles Pea- 

 body of Glenwood, I. M. R. R., that he one day expressed great aston- 

 ishment at their total and sudden disappearance. I told him that 



'* As Dr. Fitch's description of this larva is the only one I know of, and is rather incomplete, 

 I subjoin the following for the scientific reader : 



Mature Larva of Pr«R0PH0Rus periscblidacttltjs. — Average length 0.50 inch. Color pale 

 greenish-yellow. .Joints separated by deep constrictions. Each joint with a transverse row of 

 large cream-colored warts, giving rise to soft white hairs, many of which are slightly clubbed al 

 tip. Four of these warts above, and six below stigmata, the four lower smaller than the six upper 

 one.--. Tne hair.s from warts above stigmata diverging in all directions and straight, those from 

 the row immediately below stigmata decurvin^. Other short and more minute club-tipped hairs 

 spring from the general surface of the body between the warts. Head yellow, with labrum 

 slightly tawny. Logs also yellow, immaculate and very long and slender. D?scribed from nu- 

 merous living specimens. 



