1861.] 50 



black, opaque, finely pubescent with yellowish; two distinct, longitudinal furrows 

 start from the shoulders and converge towards the scutellum: between them two in- 

 distinct, glabrous, somewhat concave lines, reaching from the collare to about half 

 the distance towards the scutellum; on each side, between the furrow and the base 

 of the wing, there is a smooth, shining, glabrous stripe, distinctly concave at its 

 anterior end, which is very near tlie furrow, without however touching it: the inter- 

 val between the furrows is finely and sparsely jinnctate, which jjunctation is some- 

 what concealed by the appressed pubescence; scutellum somioval, iinely chagreen- 

 ed and pubescent, the pubescence converging towards a longitudinal, ecnfral line; 

 the two pits, usually found at the basis of the scutellum, are flat, roughly sculptur- 

 ed at the bottom; on each side of them there is a tuft of short, yellowish hairs; ab- 

 domen dark brown, shining, finely pubescent on both sides at the basis: posterior 

 margin of the second segment very oblique, the segment being much broader on 

 its dorsal than on its ventral side; feet black, more or less reddish-brown at the troc- 

 chanters, the knees and the basal joints of the tarsi, especially of the two anterior 

 pairs; wings: basal, subcostal, radial and second transverse veins very. stout, dark 

 brown, almost black; the radial one slightly arched, its tip incrassated, almost club- 

 shaped; second transverse vein very stout, angular; areolet distinct, triangular; cu- 

 bital vein distinct before and beyond the areolet, running, from it in a straight line 

 and without decreasing at all in distinctness towards the posterior margin and stop- 

 ping at a short distance before it: anal vein likewise straight and distinct; it has a 

 brown cloud a short distance beyond the basal vein : another small brown cloud is in 

 the corner formed by the radial and the cubital vein, just beyond the areolet and a 

 couple of irregular brown marks towards the tij? of the wing. Length about 0.17. 

 I have obtained the only specimens I possess by cutting the gall open 

 (in October). 



5. QuERCUS ALBA. White Oak. " Globular (/all, resevthlinij <i pea. 

 its su7-f ace finely netted loitlt fiamrcs or cracks and intervening elevated 

 points, like tlie surface of a straicherri/, oh the underside of the lefrres." 

 (A. Fitch, Reports, Vol. II. No. 310. with a figure). Cymi'S quercus 

 PISUM Fitch. 



I found these galls internally exactly as Dr. Fitch describes them, with 

 two cavities, divided by a thin partition. On the 2ord of June they were 

 lemon-yellow, reddish on one sidej the larvfe were very small. In autumn 

 the dry galls have the color of a dead leaf and preserve their shape very 

 well on account of their thick, woody shell. 



The fly obtained by me from these galls is evidently different from that 

 described by Dr. Fitch. The latter seems to be the true originator of the 

 gall, whereas mine is very likely a parasite. INly specimen, apparently a 

 male, has li-jointed antennte (Dr. Fitch's C. quercus jri^um. has 15 and 

 13 joints), and on account of the structure of its abdomen belongs to the 

 Fi(jitidae. The characters of the genus Sarothrus as given by Mr. Kein- 

 hardt (Berl. Ent. Zeit. 1860) agree with it tolerably well, except that the 

 petiole of the abdomen is striate and not smooth. 



Sarothrus ■? pisum u. sj). — Black, mouth slightly reddish: antenna* 14-jointed, 



