454 
MOLLUSCA. TEREDINADJS. 
Teiiedo- 
Gek. CYRENA. — Suborbicular, with three primary teeth in 
each valve, and transverse lateral teeth ; ligament on the 
longest side. 
1. Q. pulchra — Suborbicular convex, smooth, slender; posteriorly trun- 
cated ; one sharp-edged and two bifid teeth in each valve ; lateral teeth 
plain and obtuse.— Cyclas puicher, Sower. Min. Conch, t. Dxxvii. f. 1 . — 
Hampstead, Isle ofWight, Professor Sedgwick. 
TEREDINAD^. 
Gen. CXXXI. TEREDO. Ship Worm.— Shell orbicular, 
hemispherical, equivalve ; hinge with a long curved tooth 
in each valve, inserted under the margin ; ligament imper- 
fect, the tube open at both extremities. Burrowing in 
wood. 
^ The ear-shaped process on the inside of the valves., at the 
outer angle under the hinge., having the inner margin de- 
tached^ and forming a straight transverse edge, and the out- 
er margin much reflected. 
548. T. hipinnata. — Accessorial appendages long, linear, and 
feathered ; an oblique rib on the margin above the teeth. 
Turt. Conch. Diet. 184, t. xi. f. 38, 39, 40. ; Biv. Brit. 15.— In drifted 
timber. Exmouth. 
Diameter upwards of three quarters of an inch ; tube simple ; appendages 
about the tenth of an inch in diameter ; silvery white, with numerous pearly 
tubercles, the outer half with verticillate, lanceolate, fringed filaments. — 
This is nearly allied to T. palmulatus of Lamarck. 
549. T. malleolus. — Accessorial appendages transverse and 
mallet-shaped, with a slender point rising like a handle from 
the middle. 
Turt. Biv. Brit. 255. t. 2- f. 19. — Drifted timber, Torbay. 
Diameter about a quarter of an inch ; striae on the triangular processes re- 
mote ; the tube consists of a slight testaceous deposit on the surface of the 
chamber, the termination of which is slightly semiconcamerated. 
The ear-shaped process with the inner margin on the in- 
side furnished with a rih only, and not a detached margin, 
and the older edge is not reflected. 
550. T. navalis. — Accessorial appendages elongated and 
spoon-shaped. 
Linn. Syst. i. 1267 — Penn. Brit. Zool. iv. 147- MonU Test. Brit. 527. 
Home, Phil. Trans. 1826, 278. t. xii. f. 3. Turt. Biv. Brit. 14. t. ii. 
f. 1, 2, 3— In timber exposed to the sea; the scourge of shipping. 
