336 



GLOSSARY 



tissue, tish'o (L. texere, to weave), an association of similar cells with special 



functions to perform. 



trachea, trd'ke a (Gr. tracheia, the windpipe), a breathing tube of an insect, 

 trichocyst, trik'osist (Gr. thrix, hair; kustis, a bladder), a small hair like 



structure of certain Protozoa (see p. 62). 

 triploblastic, trip to blas'tik (Gr. triploos, threefold ; blastos, a germ), having 



three germ layers. 



tropism, tro'pizm (Gr. trope, turn), a turning caused by stimulus. 

 typhlosole, tif' Id sol (Gr. tuphlos, blind; solen, tube), a thick fold of the 



intestine of certain annelids. 



unicellular, unisefular (L. unus, one; cellula, a cell), consisting of a 

 single cell. 



uniramous, u ni rd'mus (L. unus, one ; ramus, branch), having one branch. 



uropod, u'rdpod (Gr. oura, tail ; po^^,s, foot), the last appendage of the cray- 

 fish. 



uterus, u'terus (L. uterus, the womb), a special section of the oviduct. 



vacuole, vak'fi ol (L. dim. of vacuus, empty), a minute vesicle in certain 



Protozoa. 

 vagina, vdji'na (L. vagina, a sheath), the passage leading from the uterus 



to the genital orifice in certain females. 

 ventral, ven'tral (L. venter, the belly), of or pertaining to the under side of 



the body. 

 Vitalism, vital izm (L. vita, life), a biological doctrine (seep. 24). 



zoology, zo oVoji (Gr. zoon, animal ; logos, discourse), the science of animals. 



zygote, z?got (Gr. zugon, a yoke), the body formed by the conjugation of 



two gametes. 



