THE STATE ENTOMOLOGIST. 



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■crease in size from the last to the first pair, and the larva curves the thoracic joints and is a half- 

 looper, especially when young. Average length about one inch. Described from numerous 

 specimens. 



Chrysalis. — Average length 0.37 inch ; reddish-brown^ rugose, especially on dorsum of ab- 

 dominal joints, but distinguished principally by the truncated apex, which has a large horizontally 

 Compressed ear-like horny projection at -each upper and outer edge. 



THE GRAPE-VINE PLUME— Pterophorus periscelidactylus, Fitch, 



(Lepidoptera, Alucitidae.) 



In my first Report a short account has already been given of this - 

 insect, but as it was very numerous last spring, and as I had good op- 

 [Fig, 27.] portunities of making further observations, 



I have concluded, by aid of the accompany- 

 ing figure, to give a more complete account 

 of it. 



In the earlier published Proceedings of 

 our State Horticultural Society reference is 

 occasionally made to " small grey or green 

 worms which feed on the young leaves be- 

 fore blossoming," * without any definite 

 name being given to them. Husmann, in 

 his "Grapes and Wine," (p. 80) mentions 

 similar worms, and I have little doubt but 

 that the insect referred to is the little Plume 

 we are now considering. 



Just about the time that the third bunch 

 of grapes, on a given shoot, is developing, 

 many of the leaves, and especially those at 

 the extremity of the shoot, are found fas- 

 tened together more or less closely, but generally so as to form a hol- 

 low ball. These leaves are fastened by a fine white silk, and upon 

 opening the mass and separating the leaves, one of two caterpillars 

 will generally be found in the retreat. I say one of two, because the 

 retreat made by the smallest of the Blue Caterpillars of the Vine, 

 namely, the larva of the Grape-vine Epimenis (Fig. '26, a) which we 

 have just treated of, so closely resembles that of the Grape-vine 

 Plume under consideration, that until the leaves are separated it is 

 almost impossible to tell which larva will be found. Both occur at 

 the same time of year, and both were more destructive than usual 

 the past season in the vicinity of St. Louis. In an ordinary season 

 they do not draw together the tips of the shoots till after the third 

 bunch of grapes is formed, and in devouring the terminal bud and 

 leaves, they do little more than assist the vineyardist in the pruning 



* Proceedings for 1860, p. 58, and 1861-2, p. 77. 



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