132 The Teredo, or Shipworm. [February, 
would be nearly impossible to write anything that would not bea 
repetition or quotation. The shipworms (Teredo) were known to the 
ancients, and Theophrastus, the friend and successor of Aristotle 
in the lyceum at Athens, observed their operations 350 B. C. 
The late Dr. J. Gwyn Jeffreys, in his excellent volumes on the 
mollusks of Great Britain, presents in a very concise and inter- 
esting way what is in fact a most valuable memoir on the ship- 
worm, Teredinide. 
The shipworms are diva/ves, that is to say, the complete shell 
is in two pieces, although one can form no idea of the Teredo 
from them, as the shelly part is but an insignificant portion of the 
entire animal, as you will learn from the following: 
“The Teredo * * * consists of along and nearly gelat: 
inous, worm-like body, without rings or segments, terminating 
at one end ina pairof * * * valves that somewhat resem- 
ble the two halves of a split nutshell which has had a large slice 
cut off at each side, and at the other 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 and 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 delicate organs. The body tapers gradu- 
ally to the outer or nearer end, where it becomes quite small and 
attenuated ; it contains the gullet, intestine and gills, which form 
at the outward point two cylindrical tubes, mostly of unequal 
length. The larger tube takes in infusoria or similar animal- 
cules, which constitute the food of the Teredo, as well as 
imbibes water charged with air for the purpose of respiration and 
keeping the whole fabric moist, while the smaller tube is em- 
ployed in the ejection of the water which has been exhausted or 
deprived of aeriferous qualities, and also serves to get rid of the 
woody pulp that is excavated by the Teredo. Both tubes form 
a kind of hydraulic machine. At the base of each lies one of 
the paddles often termed ‘pallets.’ * * * 
“When the Teredo is alarmed, or not feeding, it withdraws its 
tubes into the neck of its sheath or shelly cylinder; and the pal- 
lets which had been previously kept pressed against the sides, 
then spring forward and close the opening so as to form an effica- 
cious barrier against all foes,” etc. 
1 British Conchology, Vol. 111, pp. 122-184. See also the Dictionaire Universal 
d'Histoire, Vol. x11, p. 358, under the title “ Taret,’ and the Encyclopedia Bri- 
ee f ; 
tannica, Vol. XV, p. 353, under “ Mollusca.” 
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