580 [December 



cimens the abdomen becomes of an obscure, blackish color. Legs brownish 

 white or occasionally dull yellowish, in the living and sometimes in the dried 

 specimen with a silvery reflection, sometimes with only the three or four 

 terminal joints of the tarsi fuscous, sometimes in addition with the ter- 

 minal 5 of the femora superiorly fuscous, sometimes in addition with the 

 superior surface of the entire leg, except the base of the femora, fuscous. 

 Wings tinged with dusky from minute, short, appressed, dusky hairs, the 

 cross-vein between the 1st and 2nd longitudinal veins always distinct, but 

 placed close to the base of the wing. The 2nd longitudinal vein scarcely re- 

 curved at its extreme tip. Anterior branch of the 3rd longitudinal vein spriug- 

 ing from the main vein at an angle of about 135°, and generally but not always 

 traceable all the way to its origin: the entire branch recurved nearly so as to 

 describe the one half of an ellipse about .3 times as long as wide and longitu- 

 dinally bisected. Length (dried) % .10 — .15 inch, 9 (including ovipositor) .16 — 

 .20 inch. "Wing %, 9 .18— .20 inch. 



Six % , sixteen 9 , the first of which came out April 17 and the hist 



May 26, others continuing to come out for several weeks afterwards. 



The 9 9 are much more numerous, as usual in this genus, than the 



% % . 



No. 2. Gall S. strobiloides 0. S.— On S. cordata. A monothalamous gall like 

 a pine-cone, always on the ti ps of twigs when young, but often with small shoots 

 of the same year's growth surrounding it, porrect, .50 — .90 in(;h in its transverse 

 diameter, and in stunted galls where the gall-maker has perished even as small 

 as .20 inch in diameter, generally when viewed laterally with an ovate outline 

 and the tip more or less truncate, occasionally subspherical. The leaves com- 

 posing it are all sessile, closely appressed and imbricate, and all those on the 

 outside are covered with a short, dense, glaucous-white pubescence on their en- 

 tire exterior surface, and occasionally in a less degree on their interior surface, 

 and are reddish-brown inside when mature, those on the inside of the gall be- 

 coming gradually smooth and reddish-brown on their exterior basal portion, 

 and finally throughout. Towards the base of the gall the leaves are orbicular, 

 the basal ones smaller; the next leaves are obovate and with their tips in a 

 semicircle, and as they approach the tip of the gall oblaneeolate, and in the 

 inside linear-lanceolate and gradually smaller, slenderer and straighter, till 

 they finally embrace the central cell containing the author of the gall. Exter- 

 nal leaves, except towards the tip of the gall, with a number of branchino- veins 

 springing from their base, the midrib scarcely distinct from them by its supe- 

 rior size and throwing out similar branches, all of them obvious on the inter- 

 nal face of the leaf and obsolete on its external face. The tip of the twig from 

 which the leaves spring, both in this and the 4 following species, is constructed 

 as in C s. brassicoides. 



Described from 30 specimens. Very common and abundant in Rock 

 Island County, Illinois, hundreds of them occurring on, a single bush. 

 None of the leaves composing this gall are ever serrate, as in the 



