no 
MOU.USCA.i ' 
fruits, and the animal, like that of a Teredo, has two small valves, 
and as many palettes. Recent specimens are only obtained from 
the Indian Ocean, but they are found fossil in Europe* * * § . We should 
approximate to them the 
Gastroch/Ena, Spengler. 
AVhere the shells are deprived of. teeth, and their edges being wide 
apart anteriorly, leave a large oblique opening opposite to which 
there is a small hole in the mantle for a passage of the foot. The 
double tube, which can be retracted completely within the shell, is 
susceptible of being greatly elongated. It appears that they are cer- 
tainly furnished with a calcareous tube f. 
In some of them, as in the Mytili, the summits are at the anterior 
angle J ; in others they are placed near the middle §. 
They inhabit the interior of Madrepores, which they perforate. 
Two genera of Acephala furnished with tubes, have been detected 
among fossils, but the first of them, the 
Teredina, Lam., 
Has a little cuilleron on the inside of each of its valves, and a small, 
free, shield-shaped piece on the hinge ||. In the second. 
Clavagella, Lam., 
One of the valves is clasped by the tube, leaving the other, however, 
free 
A single living species is found in the Madrepores of the 
Sicilian seas, which has been described by M. Audouin. 
Some naturalists think we should also place in this family 
the 
xAspergillum, Lam., 
The shell of which is formed of an elongated conical tube, closed at 
its widest extremity by a disk perforated with numerous small tu- 
bular holes ; the little tubes of the outer range being longest, form a 
kind of corolla round it. The reason for approximating them to 
* Teredo clav'a, Gmel., Spengl., Naturfosch., XIII, 1 and 2, copied Encyc. Method., 
Vers., pi. clxvii, f. 6 — 16. It is the Fistulana gregata, Lam.; — Teredo ufriculus, 
Gm., Naturf., X, i, 10; probably the same as the Fistulana lagenula, Lam., Encyc. 
Method., I, c, f. 23 ; — Fistulana clava, Lam., Ib., 17, 22. 
It is probable that the Pholas teredula, Pall., Nov. Act. Petrop., II, vi, 25 is also 
a Fistulana. 
f This tube has been observed by Messrs. Turton, Deshayes, and Audouin. 
J Pholas Mans, Chemn. X, clxxii, 1678, 1679. 
§ Id., 1681, a very different species from the preceding, not properly distinguished 
by Chemnitz. 
II Teredina personata, Lam., and Desh., Foss, de Par. I, pi. i, f. 23, 28. 
If Cl. echinata, Lam., Ann. duMus., XII, xlii, 19, Cl. coronuta, Desh., Foss., I, v. 
15, 16. 
