Te'res ml'nor (L. tercs, rounded ; minor, smaller). A muscle 

 passing from the scapula to the humcrus. 



Ter'gal facet' (L. tergum, the back). The dorsal, smooth, 

 anterior surface of each somite in the Crustacea, on which 

 the posterior part of each previous somite moves in flexion 

 and extension of the abdomen. 



Ter'gum (L. the back). The dorsal part of the carapace in the 

 Crustacea. 



Test ") (L. testa, a shell). A term applied to the calcareous 



Tes'ta j covering of sea urchins, c. The outer coat of the 

 seed of a plant. 



Tes'tis(L. a testicle). Thegland which secretes the spermatozoa. 



Testudi'nea (L. testudo, tcstudinis, a tortoise). A group of the 

 Chelonia which comprises the land tortoises. 



Te'tanus (Gr. tetanos, tension, from teino, I stretch). The con- 

 dition of sustained contraction of muscular fibre. 



Tetrabrancbia'ta (Gr. tetras, four ; branchia, a gill). A group 

 of the Cephalopoda having four gills. 



Tetradac'tyle (Gr. tetras ^ four; daktulos, a finger or toe). 

 Having four digits. 



Tetra'merous (Gr. tetras, four; meres, a part). Consisting of 

 four portions. 



Thalamence'phalon (Gr. thalamos, a bed, couch ; cnkephahni, 

 the brain). The "inter-brain," comprising the thalami 

 optici, pineal gland, pituitary body, and third ventricle. 



IbMamus op'ticus (L. optic couch). The name of each of two 

 structures in the side-walls of the third ventricle of the 

 brain, from which the fibres of the optic tract partly arise. 



Thalas'sa-col'lida (Gr. thalassa, the sea; kolla, glue). A group 

 of Protozoa. 



Thau'motrope (Gr. thauma, a wonder; trepo, I turn). An 

 instrument in which figures in series of different positions 

 are painted near the circumference of a disc, and the 

 reflections of these, being looked at in a mirror through 

 openings in a card revolving with them, are seen in the 

 form of figures, each of which appears to perform the whole 

 movement represented in stages on the disc. 



The'ca (Gr. a sheath, envelope). Applied to the synovial 

 sheath of a tendon. Also the name given to the calcareous 

 cup in some of the Actinozoa. 



The'codont (dr. t/icke, a sheath; odous, odontos, a tooth). 

 Having the teeth lodged in alveoli ; applied to the extinct 

 Protorosauria, a group of the Laccrtilia. 



