Holcaspis brevipennata Gillette
Gall. (Plate IX, Figs. 4. 5.) Attached singly to the under side and always near the margin of the leaves of oak (Quercus undulata). Globular thin shelled; straw color more or less stained with rusty brown. The central cell is held in place by a rather abundant growth of fine radiating fibres, more or less branched toward their outer ends. Diameter 11 to 18 mm.
Habitat. Manitou, Colorado. (Gillette.)
The gall somewhat resembles that of Dryophanta polita, but is more fragile and thin shelled. The wings of the adult extend slightly beyond the abdomen. The parapsidal grooves are continuous and the anterior part of parallel lines are wanting.
The types of the adults and galls are with Prof. C. P. Gillette and in The American Museum of Natural History.
”- William Beutenmuller: (1909) The species of Holcaspis and their galls©