80 Lamarck’s Genera of Shells. 
The tubicolaria, as well as the pholades, consist essentially 
of two similar, equal and regular valves, jointed like a hinge. 
In consequence of their having accessory pieces, but which do 
not properly belong to the valves, these shells have been mis- 
taken for multivalves. 
1. Aspergillum*. 
Sheath tubular, testaceous, diminishing insensibly towards 
the anterior part, which is open; the other end larger, and club- 
shaped; near the club are two valves incrusted in the side of 
the tube ; terminal disc of the club convex, pierced with sub- 
tubular holes, and a fissure in the centre. 
Animal unknown. 
It has been erroneously supposed that the aspergillum is 
fixed to rocks by its smaller end, which is necessarily open. 
Type. Aspergillum Javanum+. (Serpula penis. Linn.) 
Sheath smooth ; posterior disc surrounded by a radiated frill. 
Indian Ocean. PI. iii. Fig. 18. 4 Species. 
2. Clavagellat. 
Case tubular, testaceous, attenuated, open at the fore part; 
the opposite extremity oval, club-shaped, rather compressed, 
with spinous tubes ; one valve fixed in the side of the club, the 
other free in the tubes. 
Type. Clavagella echinata§. 
Club of the sheath ventricose, one side covered with tubular 
spines. PI. ili. Fig. 19. Grignon. 4 Species, all fossil. 
3. Fistulanal]. 
Sheath tubular, generally testaceous, tumid, and closed pos- 
teriorly ; anteriorly attenuated, open at the summit, containing 
a free bivalve shell; valves equal, and when closed gaping. 
Neither valve fixed to the side of the tube. In some instances 
they have a slight resemblance to the valves of a modiola. 
Animal......protrudes at the fore part, or small end of the 
tube, two little calcareous pipes, each terminating in from five 
to eight funnel-shaped, semicorneous, or calcareous cups, piled 
one above the other. 
* A watering-pot. + Of Java, + Clava, aclub. § Prickly. 
|| Fistula, a pipe. 
