We are in possession of so little accurate information concerning Foraminifera of pre-Carboniferous age, that any contribution to the knowledge of the subject, however insignificant it may of itself appear, has a very distinct value. The only notices of pre-Carboniferous examples of the genus Lagena hitherto published occur in a provisional list of Microzoa drawn up by Professor T. Rupert Jones, F.R.S., and appended to a paper by Mr. J. Smith of Kilwinning, “On a Collection of Bivalved Entomostraca and other Microzoa from the Upper-Silurian Strata of the Shropshire District,” in the Geological Magazine for February, 1881; and in a brief allusion to the same specimens in the “Report on the Challenger Foraminifera” (p. 449, etc.); but iu neither case is the notice accompanied by any details.