H. F. BASSET T. 319 



The other fly belonged to the genus Neuroterus. The new Andri- 

 cus, which I call A. exiguus, is described as follows: 



Head black. Anteniije pale yellow, fourteen jointed, first joint 1 a rge, second 

 large, globular, third as long as one and two together and siibclavate, the rest 

 equal and of medium length, uot quite as long as the third, the last is very mi- 

 nute. The apical joints — 10, 11, 12, 13 — slightly dusky. Thorax shining yellow. 

 Parapsides small and distinct. Scntellntn yellow, slightly rugose, bounded pos- 

 teriorly by a heavy ridge. Fovse round and deep and near together. Abdomen 

 shining, yellowish brown. Legs pale yellow. Wings subhyaliue. Veins pale 

 brown. Areolet present but faint. Radial area open, broad. Cubitus slender, 

 reaching three-fourths the distance to the first transverse. 



Female. — Head black. Antenna? thirteen jointed, dusky brown, joints 3 to 10 

 are in dry specimens much shrunken and wrinkled. Wings not clear. Veins 

 distinct. Accurate measurements hardly possible (See Neuroterus exiguus B.). 



Aiidricus crystalliiius n. sp. 



I have received at different times from Mrs. E. H. King, of Napa 

 City, Cala., a singular species of gall which grows in clusters on 

 the leaves of Q. agrifolia? usually but not invariably on the under 

 side. Full grown galls are from .30 in length to .13 in diameter, 

 but only a few seem to reach maturity. Some are mere points. 

 They are often quite dense clusters and remind one of our common 

 A. Jiocci Walsh, by their woolly appearance, but the bright pinkish 

 wool is resolved by the magnifier into a beautiful mass of brittle 

 crystalline fibres. The largest galls terminate in an elongated neck, 

 the lower half of which is generally smooth, while the upper part 

 branches out tree-like. So far as I can discover these galls contain 

 neither woody fibre nor cellulose tissue. They bear no resemblance 

 to any ordinary vegetable growth ; but the body of the gall and the 

 crystalline frost-work that covers it have a clear, semi-transparency, 

 more or less pinkish, like beautifully tinted glass. The galls have 

 a strong astringent taste, and are nearly pure tannic acid. On 

 opening two mature galls I found two dead but fully matured gall- 

 flies. Each gall contains two chambers, one above the other, with a 

 very thin partition between them. The larva matures in the lower 

 chamber. 



The female flies, of which I have two, are .10 in. in length. 



Head black. Antennae dark reddish brown ; unfortunately the antenna? are 

 broken, but the first joint is large, club shaped, second very short and oval, third 

 as long as one and two together, fourth scarcely, shorter than the third, the rest 

 very little less in length. Thorax black and shining, hut with rather stout scat- 

 tered hairs along the usual parapsidal and median lines. Scutellum narrow, 

 rounded and corrugate. Fovse not distinct. Abdomen bla^k and sliming and 

 without hairs. Legs dark reddish brown. Wings large; veins distinct but slen- 

 der. Areolet small. Radial area open. 



TRANS. AM. ENT. SOC, XXVI. JULY 1900. 



