Open at each extremity

Abraham Rees, The Cyclopaedia or Universal Dictionary of Arts Sciences and Literature, Londres, 1808-1820.

In entomology, a name given by some authors to the larvae of the Phryganeae which are found in ditches and used as bait for fish. See Phryganeae

The Phryganeae proceed from fix-footed aquatic larvae of a lengthened shape, residing in tubular cases, which they form by agglutinating various fragments of vegetable substances, particles of gravels etc..
These cases are lined within by a tissue of silken fibres, and are open at each extremity..