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serves for the attachment of the animal to 

 the object to which it is moored, can 

 rarely be traced. The casts of some spe- 

 cies of fossil Terebratulse are of a most 

 extraordinary form. These casts are said 

 to have been first noticed by Pliny, who 

 describes certain stones, some of which 

 were white and others brown. Agricola 

 next noticed these bodies, as having been 

 found whilst digging near the fortress of 

 Ehrenbreitstein, in Treves. After various 

 opinions had been offered respecting the 

 true origin and nature of these fossils, 

 Wolfart advanced the opinion that they 

 were the casts of marine shells. Tere- 

 bratulae are found most abundantly in the 

 secondary and tertiary formations. Dr. 

 Mantell enumerates the following species 

 as occurring among the organic remains 

 of Sussex. In the chalk formation Tere- 

 bratula subrotunda, very common, T. 

 carnea, T. ovata, T. nudata, T. subplicata, 

 T. elongata, and T. plicatilis. In the two 

 last species, namely, T. elongata and T. 

 plicatilis are included as varieties T. un- 

 dulata, T. subundata, T. intermedia, T. 

 semiglobosa, T. octoplicata, and T. con- 

 cinna. In the chalk marl are found Te- 

 rebratula subrotunda, T. undulata, T. 

 striatula, T. Mantelliana, T. Martini, T. 

 rostrata, and T. squamosa. In the upper 

 green-sand, Terebratula biplicata. In 

 the Shanklin sand Terebratula ovata, and 

 T. lata. 



TEREDI'NA. (from teredo, a little worm 

 that eateth wood, Lat.) A genus of 

 acephalous testacea, belonging to the 

 family Inclusa, or, according to Lamarck, 

 Tubicolaria. The valves are equal and 

 inequilateral, with a little hollow on the 

 inside of each valve, and a small, free, 

 shield- shaped piece on the hinge. Tere- 

 dinse are known only in a fossil state. 



TERE'DO. (teredo, Lat. a little worm that 

 eateth wood ; Teprjdtjjv, from Tepew, to 

 bore, Gr.) A genus of marine bivalves, 

 belonging to the family Inclusa, in Cu- 

 vier's arrangement, and to Tubicolaria, in 

 Lamarck's. The Teredo is contained in 

 the lower end of a cylindrical tubular 

 shell, generally open at both ends, two 

 opercula being adapted to the upper end : 

 it is capable of penetrating wood. The 

 shells of this genus inhabit the bottoms of 

 ships, and wood under water. One spe- 

 cies, Teredo gigantea, has been found in 

 mud at the bottom of the ocean ; it attains 

 to a great size, one specimen measuring 

 five feet four inches in length, with a cir- 

 cumference at the base of nine inches. 

 The body of the shell had an appearance 

 resembling stalactites, and was found 

 filled with a soft gelatinous flesh. When 

 arrived at its full growth the Teredo gi- 

 gantea closes up the end of its shell. 



TERE'DO NAVA'LIS. The ship-worm. The 

 name given to a species of Teredo from 

 the circumstance of its insinuating itself 

 into the timbers of the bottoms of ships, 

 even although the oak is perfectly sound : 

 it very soon completely destroys the tim- 

 bers it attacks. This destructive creature 

 was brought originally, by our ships, from 

 tropical climates, but it has now become 

 an inhabitant of most of the harbours of 

 this country. The teredo navalis or ship- 

 worm, will destroy every thing constructed 

 of timber that is under the surface of t the 

 water. Their object is not to devour the 

 wood, but to make for themselves a cell 

 in which they may be safe from their 

 enemies. They bore in the direction of 

 the grain of the timber, deviating only to 

 avoid the track of others. Fortunately 

 these animals cannot exist in fresh-water. 



TE'RMINAL. (from terminalis, Lat.) In 

 botany, applied to flowers and umbels 

 proceeding from the extremity of the stem 

 or branches. 



TERMINO'LOGY. For an explanation of 

 this term, see Orismology. 



TE'RNA FO'LIA. In botany, leaves growing 

 three together in a whorl. This term, it 

 must be remarked, is very different in its 

 signification from ternate. 



TE'RNARY. (ternarius, Lat. of or belong- 

 ing to three; ternaire, Fr. ternario, It.) 

 Proceeding by threes ; consisting of three. 

 Applied to things arranged in order by 

 threes : thus, in botany, a flower is said 

 to have a ternary division of its parts 

 when it has three sepals, three petals, 

 three stamens, or twice or thrice as many. 



TE'RNATE. (from ternus, Lat.) A term 

 in botany, applied to compound leaves 

 that consist of three leaflets on a petiole : 

 the leaf of the strawberry affords a fami- 

 liar example of a ternate leaf. 



TE'RRA PONDERO'SA. Another name for 

 barytes. See Barytes. 



TE'RRA SIE'NNA. The name given to an 

 ochreous earth from its being brought 

 from Sienna : it is a sort of brown bole, 

 and is used as a pigment. 



TE'RRAIN TERTIA'IRE. The name given by 

 the French geologists to the tertiary 

 strata. The Germans call these, Tertiar- 

 gebilde. 



TE'RRE VERTE. Green earth. The griin 

 erde of Werner ; talc zographique of 

 Haiiy ; chlorite baldogee of Brongniart. 

 An earth of a green colour, sometimes 

 passing to olive. It consists, according 

 to Klaproth, of silex 53, magnesia 2, 

 potash 10, oxide of iron 28, water 6. 

 Vauquelin states that it contains 7'00 of 

 alumine. It is found in Germany, France, 

 Italy, and North America. It is ground 

 with oil, and used as a pigment. 



TE'RREOUS. (terreus, Lat. terreux, Fr. 



