TEREDIDA. rz3 
species, 7’. chlorotica, the pallets of which are elongated, with the 
basal portion, thin, flexuous, the upper lyre-shaped, the extreme 
two-thirds of their length being covered with a dark crust which 
has a projecting horn at each angle. The form of these pallets 
very closely resembles that of Nausitoria, when the tip is broken 
away; it may belong to the same genus. 
?TEREDOLITES, Desh. For a cretaceous species, 7. clavatus, 
only known by some tubes which are short, clavate, and in posi- 
tion, as they occur in the rock or wood, almost parallel to each 
other. 
[poLortHus, Gabb. See page 53, vol. ii. ] 
Xyutorrya, Leach, Gray, 1847. 
Syn.—Bankia, Gray. 
Distr.—10 or 12sp. Universal. X. palmulata, Lam. (cv, 74). 
KE. Indies. 
Siphonal pallets elongated and penniform, the blade con- 
sisting of articulated pieces radiating obliquely from the style. 
A species occurs in the fossil wood of the Greensand of Black- 
down, England. 
Urrrotis, Guettard, 
Syn.—Guettera, Gray. 
Distr.— U. clava, Gmel. (civ, 49). Tranquebar. 
Tube club-shaped, straight or contorted, growing together in 
masses ; pallets oval, jagged; valves narrow and elongated. 
Kupuus, Guettard. 
Syn.—Furcella and Septaria, Lam. Clauseria, Menke. 
Distr.—K. arenarius, Linn. (civ, 50-52). Philippines. 
Tube penetrating sand, somewhat irregular, very large; 
pierced around the base with small scattered perforations, and 
inclosed by two overlapping convex septa arising from the sides 
and completely closing the end. These septa appear to replace 
the valves. 
The tube of the giant Teredo is often two yards long and two 
inches in its greatest diameter; when broken across it presents 
a radiating prismatic structure. The siphonal end is divided 
lengthwise, and sometimes prolonged into two diverging tubes. 
TEREDINA, Lam., 1818. 
Distr.—T. personata, Lam. (civ, 53,54). Hocene; Europe. 
Valves with an accessory plate in front of the umbones; free 
when young, in the adult connected with the tube. The tube 
is sometimes concamerated ; its siphonal end is often truncated ; 
and the opening contracted by a lining which makes it hour-glass 
shaped, or six-lobed. 
The possession of an accessory dorsal valve connects this genus ~ 
with the next family; no siphonal pallets have been discovered. 
