61 



The Grape leap Trumpet-gall — (Filis viiicola 



Ceculomyidm. 



0. S.)— Order Diptera. Family 



This ia another, more regular gall, made by a sjall-gnat which has not yet been described, 

 is elongate, conical, and grows more or less numerously from the surface nf the leaf, look- 

 ing somcthini; like a small trumpet. (Fig. 41) 

 I have found it on both wild Cordi folia and 

 Riparin, and it doubtless occurs on their cul- 

 tivated varieties. It is also found on Labrusca 

 and Vulpiiia. (See A. E., II. p. 28.) Th» 

 usual colour is a bright crimson, but it some- 

 times inclines to green ; especially when young 

 or on the under side of the leaf ; for though 

 it is more often found on the upper side, I 

 have met with it antijiosed. Upon cutting 

 into these galls, we shall find them to be hol- 

 low, and each to contain a pale orange larva, 

 Trhich probably resembles those already men- 

 tioned in transforming under ground. The 

 gall was at first briefly described by Baron 

 .Osten Sacken (Diptera of N. A., part I., 

 ,T). 202). Similar but distinct galls grow on 

 the leaves of Hickory and Hackberry, but are 

 always green. 



