THU 



415 



TIB 



are found to consist of a vegetable 

 fungus, viz. the Oidium albicans. 

 Thuja, n., thu'-ja (Gr. thutin, in- 

 cense, perfume), a genus of 

 aromatic plants, Ord. Coniferse, 

 Sul -ord. Cupressinese : Thuja 

 articulata, drt-fkf-ul-at'.tf, (L. 

 articuldtus, furnished with joints, 

 distinct), the Arar tree, which 

 supplies a solid resin called 

 Sandarach or Pounce, used to 

 strew over MRS. : T. occidentalis, 

 dkf'Sid-ent'dl'is (L. occidentdlis, 

 western), the common Arbor vitse 

 of gardens so named from its 

 supposed medicinal qualities : T. 

 orientalis, or'-i-Znt-dl'-is (L. ori- 

 entdlis, eastern), a species also 

 cultivated : Thus, thus (L. thus, 

 or tus, incense), common frankin- 

 cense, yielded by Finns palustris 

 and P. tseda, Ord. Coniferse. 

 Thymelseacese, n. plu., thim-We-d'- 

 se>e (L. thym$lcea, the flax-leaved 

 Daphne plant), the Daphne 

 family, an Order of plants, the 

 bark of many of which is acrid 

 and irritant, and the fruit is 

 often narcotic ; see ' Daphne. ' 

 thymus, n., ihlmf-us (Gr. thumdn, 

 a fleshy excrescence on the skin), 

 a temporary organ of childhood, 

 consisting of two lateral lobes, 

 placed partly in the neck, and 

 extending from the fourth costal 

 cartilage upwards, as high as the 

 border of the thyroid gland ; it 

 attains its full size at the end of 

 the second year, after which it 

 gradually dwindles, and almost 

 disappears at puberty. 

 thyro-, thir f -o, and thyreo-, thlr'-$-d 

 (Gr. thuretis, a shield), a prefix in 

 anatomical terms denoting con- 

 nection with the thyroid cartilage : 

 thyroid, a., thlr'-dyd (Gr. eidos, 

 resemblance), applied to one of the 

 cartilages of the larynx, so named 

 from its shield-like form ; applied 

 also to a glandular body lying in 

 front of this cartilage, or to the 

 arteries supplyingthe part ; denot- 

 ing the large bone at the bottom 



of the trunk, from its shield-like 

 shape : thyro -arytenoid, -ar'it'en'- 

 oyd, a ligament, consisting of a thin 

 band of elastic tissue, attached in 

 front to the angle of the thyroid 

 cartilage below the epiglottis, 

 and named the superior or false 

 vocal cords : inferior thyro- 

 arytenoid, two strong fibrous 

 bands, each consisting of a band 

 of yellow elastic tissue, attached 

 in front to the depression between 

 the two alse of the thyroid cartil- 

 age, and behind to the anterior 

 angle of the base of the arytenoid, 

 and named the inferior or true 

 vocal cords. 



thyrohyal, a., tftfrto-A&B (Gr. 

 thureos, a shield, the U-shaped 

 bone ; see 'hyo'), applied to two 

 ossifications of the hyoid in the 

 lower vertebrata ; homologue of 

 the larger horn of the hyoid bone 

 in man. 



thyrsus, n., thers'>us, also thyrse, 

 n., thers (L. thyrsus, Gr. thursos, 

 a stalk, a stem), in bot., a species 

 of inflorescence ; a very compact 

 pannicle, as the flowers of the 

 lilac, or as having the appearance 

 of a bunch of grapes. 

 Thysanura, n. plu., this'an>ur'a 

 (Gr. thusanoi, tassels, fringes ; 

 our a, a tail), an Order of Apterous 

 Insects: thysanurous, a., this'* 

 dn'Ur^uSj having fiing'd tails. 

 tibia, n., tib'-i-d (L. t-na, a pipe 

 or flute), the larger of the two 

 bones of a leg, so called from its 

 supposed resemblance to an 

 ancient flute the upper part 

 resembling the expanded or trum- 

 pet-like end, and the lower the 

 flute end ; the shin - bone : 

 tibialis anticus, tib'-i-dl'is ant- 

 ilf-us (L. tibialis, of or pert, to the 

 shin-bone ; anticus, in front), the 

 fore part of the tibial muscle ; 

 one of two muscles of the tibia 

 which bend the foot by drawing 

 it upwards, etc.: the other is 

 tibialis posticus, tW-l-dl'-is pdst- 

 ik'us (L. posticus, behind the 



