TEREDIDA. 1A | 
three-lobed, concentrically striated, and with one transverse 
furrow ; hinge-margins reflected in front marked by the anterior 
muscular impressions; umbonal cavity with a long, curved, 
muscular process. 
Animal worm-like; mantle-lobes united, thickened in front, 
with a minute pedal opening; foot sucker-like, with a foliaceous 
border; viscera included in the valves, heart not pierced by the 
* intestine; mouth with palpi; gills long, cord-like, extending into 
the siphonal tube; siphons very long, united nearly to the end, 
attached at the bifurcation and furnished with two shelly pallets 
or styles; orifices fringed. 
T. navalis is ordinarily a foot long, sometimes two and a half 
feet; it destroys soft wood rapidly, and teak and oak do not 
escape; it usually bores in the direction of the grain, unless it 
meets the tube of another Teredo or a knot in the timber. In 
1731-2 it did great damage to the piles in Holland, and caused 
still more alarm: metal sheathing and broad-headed iron nails have 
been found most effectual in protecting piers and ship-timbers, 
The Teredo was first recognized as a bivalve mollusk by Sellius, 
who wrote an elaborate treatise on the subject in 1733.—ForBEs. 
T. corniformis, Lamarck, is found burrowing in the husks of 
cocoa-nuts and other woody fruits floating in the tropical seas ; 
its tubes are extremely crooked and contorted, for want of 
space. The fossil wood and palm-fruits (Mipadites) of Sheppy 
and Brabant are mined in the same way. 
T. Norvegica and T. nana are divided longitudinally and also. 
concamerated by numerous, incomplete, transverse partitions at 
the posterior extremity of the tube. 
I annex Dr. J. Gwyn Jeffreys’ excellent account of this 
mollusk : 
“The Teredo is an anomaly. It consists of a long and 
nearly gelatinous worm-like body, without rings or segments, 
terminating at one end in a pair of hemispherical valves, that 
somewhat resemble the two halves of a split nutshell which has 
had a large slice cut off at each side, and at the other end ina 
pair of symmetrical shelly paddles with handles of different 
lengths, which close this extremity at the will of the animal. 
The open part of the bivalve shell is placed at the further end, 
and receives a circular disk, of a fleshy or rather muscular 
nature, which may be termed the foot; this is the broadest or 
widest part. Inside each valve is seen a curved process, like a 
bill-hook, that projects from the hinge at a right-angle. The 
shell covers and protects the mouth, palps, liver and other deli- 
cate organs. The body tapers gradually to the outer or nearer 
end, where it becomes quite small and attenuated ; it contains 
the gullet, intestines and gills, and is enveloped in a thin mem- 
brane or mantle, which forms at the outer end two cylindrical 
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