CONCHOLOGY. 
with two valves covering the head of the animal, 
and two lanceolate ones near the tail, 
1, Teredo navalis. Donovan, pl, 145.— Turton, 
t. 2. fig. ¥. 3. 
Occasionally found in oid stakes, and the bottoms 
of ships. 
2. T. bipennata, Turion Dict. fig. 38 to 40, 
3. T. malleolus. Turton, t. 2. fig. 19. 
4, T. nana. Turton, t. 2. fig. 6. 7. 
The three last discovered by Dr. Turton, in sub- 
marine wood, 
AYLOPHUAGA., 
Shell Iodged in wooed, resembling the Teredo, 
except its wanting the long curved teeth within the 
valves, and the long tube with its accessorial valves, 
instead of whieh there are two curved calyx-like 
valves behind the hinge. 
I. Xylophaga dorsalis. Turton’s Bivalves, tab. 
2. fig. 4. 5. 
This new and singular genus was first distin- 
guished by Dr. Turton, in masses of wood which 
had long lain under water in Terbay. 
