Lamarck asserts that the tube and shell of this genus are quite
distinct. It so greatly resembles the Teredo that it is with difficulty
distinguished. It is found in sand, wood, stone, and sometimes shells.
Shell annular or very short, not sharp nor angular anteriorly, but in
other respects much like that of the Teredo.
Tube generally shorter, thicker, more solid, more club-shaped than that
of the Teredo, always closed at its anterior extremity in such a manner
as to contain and entirely hide the shell; the posterior extremity open,
and divided interiorly into two syphons by a partition.
Fistulana clava.
F. corniformis.
F. gregata.
F. lagenula.
_F. corniformis._ The horn-shaped Fistulana.
Answers to the above description.
_F. gregata._ The gregarious Fistulana.
Sheath or tube doubly club-shaped, congregating; shell angularly
arcuated, with double angulated serrated wings.
_F. Clava._ The Club Fistulana. Pl. 33, fig. 5.
Species with one end clavate, the other incurved, narrower, obtuse, and
perforated in the middle; shell generally flexuous, of a brownish
colour; exterior rough, interior smooth.