Dactylosphaera depressum, n. sp.
Gall No. 4

Hosts: Carya alba [tomentosa]

These galls were found to be exceedingly numerous on some trees. On June 20th, they were smooth, slightly rounded above, pale yellowish-green; beneath somewhat whiter, and having in the centre a nipple-like projection; opening round, surrounded with a burr- like fringe composed of many filiments,the cavity like an inverted cone, the wall above being quite thin and translucent, so that the inmates may be seen moving about. This apparently very flat gall was placed as much below as above the plane of the leaf. Diameter .15 — .25 inch ; vertical thickness .125 inch.

- Henry Shimer: (1868) A summers study of hickory galls, with descriptions of supposed new insects bred therefrom^©

Reference: https://www.biodiversitylibrary.org/item/54546#page/441/mode/1up