390 GLOSSARY 



Sensory nerves : nerves which carry impulses resulting in sensation. 

 Se'rous : pertaining to serum ; filled with, or secreting serum. 

 Se'rum (Lat., akin to Gr. oros, Skr. sara, curd) : the watery portion 



of certain animal fluids, as blood, milk, etc. 

 Skull : the skeleton of the head. 

 So'di-um (Eng. soda) : a chemical element found in union with 



various acids. 

 So'lar plexus: a network of nerves about the pit of the stomach, 



containing fibers from many different nerves. 

 Spec'trum (Lat., an appearance, image) : the several rays of which 



light is composed separated by refraction and spread out in a band 



of colors and dark lines. 

 Sphe'noid (Gr. sphenoeides, wedge-shaped) : an irregularly shaped 



bone in front of the occipital in the base of the skull. 

 Sphinc'ter (Gr. sphigkter, anything which binds tight) : a muscle 



which surrounds and tends to close a natural opening. 

 Spi'nal (Lat. spina, the spine) : pertaining to the backbone. 

 Spinal ac-ces'so-ry nerves : the eleventh pair of cranial nerves. 

 Spinal cord : the cord of nervous matter lying in the channel of the 



vertebral column, and continuous with the nervous matter of the 



brain. 



Spiral ganglion : a mass of nerve cells in the inner ear. 

 Spleen: one of the ductless glands, lying in the abdomen near the 



stomach. Of its functions little is positively known. 

 Spleen pulp : a soft substance in the meshes of the tissue of the spleen. 

 Splen'ic : pertaining to the spleen ; as the splenic vein. 

 Spu'tum (Lat., from spuere, to spit): that which is expectorated or 



discharged from the lungs. 

 Sta'pes (Lat., a stirrup) : the innermost of the auditory ossicles, 



shaped like a stirrup. 

 Ster'il-ize (Lat. sterilis, barren) : to render incapable of germination ; 



to make sterile ; to destroy the germs in food or water. 

 Ster'num (Gr. sternon, the breast) : the bone in the middle of the front 



of the chest. 

 Stim'u-lus (Lat. for stigmulus, akin to instigare, to prick, to goad): 



any substance or agent capable of arousing the activity of a nerve 



or irritable muscle, or capable of producing an impression upon a 



sensory organ. 



Stro'ma (Gr., a couch) : the colorless framework of a red blood cor- 

 puscle or other cell. 



