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Show 2 MR. BARKER ON TEREDOS FROM SUBMARINE CARLES. [Jan. 14, bronzy green; outer secondaries grey, with a large blotch of brownish chestnut on their outer webs ; tail black ; breast and belly dark grey, with numerous white cross-bars ; crissum rufous ; under tau-coverts white ; bill brown; feet yellowish : whole length 18 inches, wing 11*8, tail 4'4, tarsus 2. A set of small Birds' bones, obtained from beneath the deposits of nitrate in Southern Peru, transmitted to the Society by Prof. W . Nation, C.M.Z.S., of Lima, Peru, was exhibited previously to being sent to the British Museum in accordance with Prof. Nation's instructions. Mr. D. Wilson Barker, F.Z.S., exhibited some specimens of Teredos taken from submarine telegraph-cables off the Brazilian coast, and made the following remarks :- " The presence of the Teredo in submarine telegraph-cables is well known to electricians, but, so far as I am aware, the attention of zoologists has not been drawn to it. With the permission of Major Wood (Managing Director of the Western and Brazilian Telegraph Company), I am able to lay these specimens before the Society this evening. They were taken out of the cable between Rio de Janeiro and Bahia, in latitude 22° 11' S., longitude 40° 22'W., from a depth of 20 fathoms. "The nature of the ' faults ' caused by these mollusks makes them very difficult to locate, so much so, that on this particular occasion we hove iu the cable a mile past them, and only discovered their presence by cutting the cable in several places, as there was no sign on the outside of the cable to show their presence inside. The specimens of cable exhibited illustrate exactly the position of the Teredos in it, and it will be observed that they must have penetrated the sheathing-wires when in the embryonic stage.and then planted themselves on the jute, into which they afterwards bored. The jute is tanned before it is laid on the internal core by a special process, and it is therefore a remarkable thing that these mollusks should be able first to bore through this tough and yielding material impregnated with a chemical solution, and then scoop out pieces in the gutta-percha sheathing of the conductor. With the Teredo was another bivalve, and the minute hole in one of the teredo-valves shows the presence of a boring mollusk. "I may also mention I have found specimens of a small Pholas in another cable, but the sheathing-wires in this case had been bird-caged out, and freely admitted water to the jute sheathing. "Apart from the interest there is in finding the Teredo adapting itself to bore into such intractable substances as jute and gutta-percha in close contact, it is a matter of serious import to the owners of cables, and the discovery of a method of preventing their attacks would be very valuable." |