According to Mr. Allman, its habits can be very easily watched, as if it is merely placed in a tumbler of sea water, together with a piece of wood, it will forthwith proceed to work, and gnaw its way into the wood. The apparatus with which it works this destruction is a kind of file or rasp, which reduces the wood into minute fragments. In this creature the jaw feet are furnished with imperfect claws, and the tenth segment from the head is curiously prolonged into a large and long spine. The great flattened appendages near the tail seem to be merely used for the purpose of cleaning its burrow of wood dust which is not required for food. The creature always swims on its back, and when commencing its work of destruction, clings to the wood with the legs that proceed from the thorax. The wood-boring shrimp is one of the jumpers, and, like the sand hopper, can leap to a considerable height when placed on dry land. It has been detected in timber taken from the sea at Trieste. It was first observed as an inhabitant of the British seas several years ago, by Mr. Robert Ball, of Dublin, and in January, 1847, it was described by Mr. Mullins, C.E., in a paper read before the Institution of Civil Engineers of Ireland, as being very injurious to the timber piles in Kingstown Harbour, near Dublin, and far more destructive than the _Limnoria terebrans_. [Illustration: LIMNORIA TEREBRANS. FEMALE. MALE. A. B. C. HEAD OF THE TEREDO NAVALIS. RASP OR FILE OF THE CHELURA. CHELURA TEREBRANS. ELEVATION OF PILES, SOUTHEND PIER, DESTROYED BY THE “TEREDO” AND “LIMNORIA” ABOVE AND BELOW THE COPPER SHEATING.] We have already referred to the _lesson_ the celebrated engineer, Brunel, received from observing the _teredo_; and we can state that architects have also received _lessons_ from nature. Sir Christopher Wren constructed his spire of St. Bride’s Church, London, after observing the construction of the delicate shell, called _Turretella_, which has a central column, or newel, round which the spiral turns. Brunelleschi designed the dome of Sta. Maria, at Florence, after studying the bones of birds and the human form; and Michael Angelo followed Brunelleschi in constructing the dome of St. Peter’s, Rome.[19] The LEPISMA is also a destructive little animal, which begins to prey on wood in the East Indies, as soon as it is immersed in sea water. The unprotected bottom of a boat has been known to be eaten through by it in three or four weeks. These worms, it must be remembered, do not live except where they have the action of the water almost every tide, nor do they live in the parts covered with sand. The wooden piles of embankments and sea locks suffer very much from their depredations, and in the sea dykes of Holland they cause very expensive annual repairs.