TOR 



[439 ] 



TEA 



TOENATE'LLA. A genus of oval, spi- 

 rally grooved, marine, univalves, 

 belonging to the family Plicacea. 

 Eecent tornatellffi are found in 

 shallow water, creeping on sands, 

 and leaving furrows. Several spe- 

 cies are found in the oolite and 

 super] acent strata. 



TOEO'SE. | (torosus, Lat.) Swelling 



TO'EOUS. j into knobs or protuber- 

 ances. A term used both in botany 

 and conchology. 



TOBPE'DO. (torpedo, Lat. from torpeo, 

 to benumb.) A subgerms of ashes, 

 belonging to the genus Raia. The 

 torpedo is found fossil in the ter- 

 tiary formations. The torpedo is 

 furnished with an electrical appa- 

 ratus, resembling the voltaic bat- 

 tery, which it has the power of 

 charging and discharging at plea- 

 sure. The benumbing effect pro- 

 ducible by the torpedo depends on 

 certain singularly constructed or- 

 gans composed of membranous 

 columns, filled from end to end 

 with laminae, separated from each 

 other by a fluid. 



TO'ERELITE. A new mineral brought 

 from the United States, and thus 

 named after Dr. Torrey. 



TO'ETOISE. (tortue. Pr.) An order 

 of the class Reptilia, or reptiles ; 

 tortoises are also termed Cbelonians. 

 The chelonians, or tortoises, were 

 all included by Linnaaus in one 

 genus, namely, testudo ; they are 

 now divided into five subgenera. 

 1. Testudo, or land- tortoise ; 2. 

 Emys, or fresh- water tortoise; 3 

 Chelonia, or sea- tortoise ; 4. Che- 

 lys; 5. Trionyx, or the tortoise 

 with a soft shell. 



The Testudo Indicus, a species 

 of land tortoise, sometimes attains 

 to an immense size, so as to require 

 six or eight men to lift it from the 

 ground, and affording as much as 

 two hundred pounds of meat. 



This order of reptiles, geologists 

 inform us, began to exist at about 

 the same period with the order of 



Saurians, and has continued from 

 that time to the present. No fossil 

 remains of the tortoise have been 

 discovered in any strata not more 

 recent than the coal formations. 



TO'EALOSE. In entomology, a surface 

 with but few elevations, scattered 

 about, but these of considerable 

 size. 



TOU'EMALINE. } A mineral divided by 



TOT^EMALIN. j some mineralogists 

 into two sub-species, schorl and 

 tourmaline ; by others, tourmaline 

 is regarded as a sub-species, or va- 

 riety of schorl. The tourmalin of 

 "Werner ; the tourmaline verte of 

 Hany ; the schorl electrique of 

 Brochant. It is of various colours, 

 the shades of some of which are so 

 dark as to approach nearly to black : 

 hardness about 7*5. Sp. gr. from 

 3-0 to 3-2. By friction it yields 

 vitreous electricity ; by heating, 

 vitreous electricity at one extrem- 

 ity and resinous electricity at the 

 other, the termination, according 

 to Haiiy, which presents the 

 greatest number of planes, exhibit- 

 ing the positive, or vitreous, elec- 

 tricity, the termination which con- 

 sists of the smaller number of 

 planes exhibiting the negative, or 

 resinous, electricity. It occurs but 

 seldom massive, most frequently 

 crystallized; its primary form is 

 an obtuse rhomboid of 133 50', 

 and 46 10'. It occurs imbedded 

 in granite, gneiss, mica slate, &c., 

 in Scotland, Sweden, America, 

 Spain, and other parts. 



TBA'CHEA. (trachea, Lat. from rpa^v^ 

 Gr. rough.) 



1. The windpipe, or that canal 

 which leads from the throat to the 

 lungs. 



2. In botany, the vessels of plants 

 in which the internal fibres run in 

 a spiral direction; they are also 

 called air-tubes. 



TEACHEA'ETA. The third order of the 

 class Arachnida : the acarus is an 

 example. 



