CECIDOMYIA. 193 



Early in summer I frequently found a gall of the same form, but 

 smaller, generally reddish at the tip and easily distinguished by the 

 absence of the basal piece in which the other is inserted ; it is 

 simply fastened to the leaf by a minute pedicel. Besides, it occurs 

 always singly, frequently on the edges of the leaves, whereas the 

 other gall is for the most part found in clusters. Is it the same 

 species? 



5. G. holotricka, n. sp. Subglobular, pubescent, onion-shaped 

 galls. Diam. up to 0.1 or a little more. 



They resemble the galls of D. caryce in shape, but are somewhat 

 larger and covered with a pubescence which is pale when the gall 

 is young and growing, and becomes rust-colored in the stage of 

 ripeness. I have observed two modes of occurrence of these galls ; 

 either they are scattered in numbers, as many as a hundred on the 

 same leaflet, or they grow in a row along the mid-rib of the leaflet ; 

 in the latter case they are generally larger, and being packed close 

 together, assume an irregular shape. It is very probable that these 

 two forms belong to two different species, and in this case I would 

 retain the above name to the first form. Galls of the first form 

 begin to grow in June ; in September and October I found the 

 white larva apparently full grown. The breast-bone has one elon- 

 gated point anteriorly and two projections on both sides, about the 

 middle. At the -same time I find in my diary that in some of these 

 galls (it is not distinctly stated which), I had found & pale orange, 

 apparently full grown larva, with the breast-bone ending anteriorly 

 in two triangular points with a rectangular excision between them. 



6. G. persico'ides, n. sp. Gall round, 0.1 to 0.2 in diameter, 

 smooth, without nipple-shaped tip, yellowish or red, clothed with 

 a delicate down like that of peach, and looking somewhat like a 

 diminutive fruit of this kind. I found these galls more seldom 

 than the others. 



1. G. cynipsea, n. sp. Rounded, irregular, hard swelling on 

 the under side of the hickory-leaf, on the midrib, near the base of 

 the leaf, about half an inch long. When I found it (in July) it 

 was pale yellowish, and contained, in several small hollows, minute 

 whitish larvaj, with a breast-bone narrowed anteriorly and ending 

 in a point. 



8. C. (jlutinosa, n. sp. The small yellowish-orange larva forms 

 no gall, but lives in the open air on the under-side of the leaf, to 

 which it is attached by a viscous substance probably secreted by 

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