The Conchologist's First Book / A System of Testaceous Malacology, Arranged Expressly for the Use of Schools, in Which the Animals, According to Cuvier, Are Given With the Shells, a Great Number of New Species Added, and the Whole Brought Up, as Accurately as Possible, to the Present Condition of the Science.

by Edgar Allan Poe; Thomas Brown

Filament, a thread-like process.

Filiform, thread-shaped, slender.

Fimbriated, fringed.

Fissure, a cleft or slit.

Flexuous, zigzag, with angles widening.

Flexure, a bending.

Fluviatile, belonging to fresh water.

Foliaceous, lamina or leave-shaped.

Fragile, brittle, easily broken.

Front, the aperture next the observer.