27 SEPTEMBER 1919, Page 13

" FORMACEAN."

[To THE EDITOR or THE " SPECTATOR.") SIR,—Replying to your inquiry last week as to the derivation of " formacean," I may point out that Pliny explains that parietes formacei " are so called " quoniam in forma, cir- cumdatis utrimque duahus tabulis, inferciuntur "—i.e., as I understand it, because they are made of material rammed clown in a mould, or case, between two sets of planks.—I am,