TRI 



725 



TRI 



angles. 2. In astronomy, & voastella- 



tion in the northern hemisphere. 3. In 



music, a small steel triangular instru- 

 ment of percussion, open at one of its 

 corners, and struck with a small steel 

 rod. 



TRIAN'GUT.AR COMPASSES. Compasses 

 having three legs, vhich open so as to 

 take off any three j/jints. 



TRIBOM'ETER, from rfiSet, to rub, and 

 fAiTgor, measure. An instrument for 

 measuring the amount of friction in rub- 

 bing surfaces. 



TRIBU'NAL. A judgment seat in the 

 forum at Rome: applied to any judg- 

 ment seat. 



TIU'CEPS, Lat. from tres and caput ; 

 three-headed. Applied to muscles. 



TRI'CHECUS. The morse: a genus of 

 amphibious mammalia of the order Car- 

 naria. Name invented by Artedi. Only 

 one species is known, the Sea Cow (T. 

 rosmarus, Lin.), which inhabits the Arctic 

 seas, and surpasses the largest ox in size. 

 It lives on fucus and animal matters, and 

 is much sought after for its oil and tusks. 

 See SEA Cow. 



TRICHI'ASIS, from r%i%, hair. 1. A 

 disease of the eyelashes, in which they 



are turned inwards. 2. A disease of 



the hair : plica. 



TRICHIU'RUS. A genus of acantho- 

 pterygious fish, belonging to the family 

 Tee/wides. Name from T/|, a hair, and 

 ou%, a tail : the tail being drawn out 

 into a long slender filament like a hair. 

 The species resemble beautiful silver 

 ribands. 



TRICHOP'TERANS, from S-^jJ and ?ro. 

 a wing. The name of an order of inseccs 

 having four hairy membranous wings. 



TRICHO'SIS. T^<%acr/s, from T/|. hair. 

 A generic name for all diseases of the 

 hair. 



TRICHC'RIS. A genus of intestinal 

 worms: named le t-er <J queue by the 

 French, two-thirds being; tail. 



TRICOC'CJS. A natural order of plants, 

 comprising such as are three-seeded (tri- 

 CYXVMS.) 



TRI'COLOR. The national French ban- 

 ner of three colours, blue, white, and 

 red, adopted on the occasion of the first 

 K evolution. 



TRICOC'COCS, Lat. tricoccus, three-seeded. 



TRICUS'PID, \ Lat. trifus/iiilatns, 



TRICUS'PIDATE. ( three-pointed. 



TRICUS'PID VALVE. The right ventricle 

 of the heart. 



TRIDAC'TYLOBS, Lat. tridactylus, three- 

 toed. 



TRI'DENT, from tridens, three-toothed. 

 The three-forked sceptre of Neptune. 



TRI'INS. A Roman copper coin, worth 

 **;- third of an at 



TRIETE'RIS. A Grecian cycle, consist 

 ing of 12 months of 30 days each. 



TRIF'ID, Lat. trifidus, three-cleft. 



TRIFO'LIATE, Lat. trifoliatus, three- 

 leaved. 



TRIFO'LIUM. Trefoil. A genus of papi- 

 lionaceous plants. Pentandria Monoijy- 

 nia. Name from ires and folium, because 

 it has three leaves on each stalk. 



TRIFO'RICM. In Gothic architecture, an 

 arched story, between the lower arches 

 and the clerestory, in the aisles of a 

 church. 



TRir/AMons, from T|5<?, three, and 

 yae^a?, marriage. Plants containing three 

 sorts of flowers in the same head. 



TRIGEM'INI. Nervi innominati. The 

 fifth pair of nerves. 



TRIG'LYPH, from rg/yAai^of , a thrfo- 

 sculpture ornament. An ornament of 

 the Doric frieze, consisting of three 

 parallel niches, and supposed by some 'a 

 represent the ends of beams. 



TRI'OON. T^iyavav- A triangle. 



TRIGONEL'LA. Fenugreek. A genus of 

 papilionaceous plants. Diadelphia J>- 

 candria. Temperate and cold climates 

 Name dim. of trigona, in allusion to its 

 little triangular flower. 



TRIGO'NIA. The name given by Bru- 

 guieres to a genus of testaceous acephala 

 of the oyster family. Living trigoniae 

 are nearly related to the cockle, but the 

 fossil species differ considerably. Named 

 from the trigonal shape of the shell. 



TRIGONOCEPH'ALCS. Serpents which 

 have a horny conical process at the tip 

 of the tail. 



TRIGONOMETRY, from ryyovos, a tri- 

 angle, and [4,tT%ov, measure. The science 

 which teaches the mensuration of tri- 

 angles, whether plane or spherical. 



TRIGY'NIA, from r%ti(, three, and yvtv;, 

 a female. The name of an order of plants 

 in the Linnaean system, distinguished by 

 the flowers having three styles or pistils. 



TRI'RILATE, Lat. trihilatus. Having 

 three hila or scars. Applied to seeds. 



TRILAT'ERAL, from tres and lattis, a side. 

 Having three sides. 



TRILL, Ital. trilla. In music, a plain 

 shake upon a simple note. 



TRILLO, Ital. In msic, to beat quickly 

 on two notes, in conjoint degrees, alter- 

 nately one after the other. 



TRI'LOBATE, Lat. trilobattts. Three 

 lobed. 



TRI'LOBITES. 1 family of fossil crusta 

 ceans, long conibunded under the namr 

 of Entomnlithut pa>-adonis, and still 

 named by some rituralists Entomostra- 

 cites. Brongniart has divided them into 

 five general Agnottm, Calymene,Aiaphus, 

 l)tjygia, and Paradoxides. They are, ac- 

 cording to Curler, the original stock ol 



