GLOSSARY 427 



Ster'ilize (Lat. sterilis, barren) : to destroy bacteria and other organisms, 

 usually by heating. 



Stig'ma (Gr. stigma, the prick of a pointed instrument) : the part of a pistil 

 which receives the pollen grains. 



Stim'ulant (Lat. stimulus, a goad) : a substance which causes temporary ac- 

 tivity of nerve or muscle. 



Stim'ulus (Lat. stimulare, to incite) : an agent which causes an organism or 

 some part to react when affected by it. 



Stip'ule (Lat. stipula, stem) : a leaflike outgrowth at the base of the petiole. 



Sto'ma (pi. Sto'mata) (Gr. stomu, a mouth) : a breathing hole in a leaf. 



Stom'ach (Gr. stomachos, throat) : a sac-like part of the food tube between 

 gullet and intestine. 



Suc'cus enter'icus : fluid secreted by glands in the small intestine, an aid to 

 digestion. 



Sweat glands : excretory glands in the skin. 



Swim'merets : paired appendages on the abdomen of crustaceans. 



Symbio'sis (Gr. symbiosis, a living together) : a condition in which two organ- 

 isms of different kinds live together in a mutually beneficial partnership. 



Synapse' : contact between the end arborization of one neuron and the den- 

 drites of another neuron. 



Tac'tile corpuscle (Lat. tangere, to touch) : sense organ of touch. 



Tar'sus (Gr. tarsos, sole of foot) : the ankle bones ; also the last region of the 

 leg of an insect. 



Taste bud : end organ of taste found on the tongue. 



Teeth : limy structures in the mouth of man and other animals, consisting 

 of incisors or cutting teeth ; canines, tearing teeth ; and molars and pre- 

 molars, crushing and grinding teeth. 



Ten'don (Lat. tendere, to stretch) : a band of connective tissue attaching mus- 

 cle to muscle or muscle to bone. 



Ten'tacle (Lat. tentaculum, a feeler) : a flexible organ at the anterior end of 

 an animal used for feeling, grasping, etc. 



Tes'ta : the thick outer coat of a seed. 



Tes'tes (Lat. testis) : sperm-producing glands. 



Thorac'ic : pertaining to the chest region. 



Tho'rax (Gr. thorax, the chest) : the part of the body between the head and 

 the abdomen. 



Tissue (Fr. tissu, a web) : a collection of cells all more or less alike and having 

 the same function. 



Tox'ins : poisons produced by bacteria. 



Tra'chea (Lat. trachia, windpipe) : the windpipe ; also a respiratory tube 

 of insects. 



Transpira'tion (Lat. trans, through ; spirare, to breathe) : the giving off of 

 water vapor from plants. 



