GLOSSARY 401 



Rhynchocephalia {ring' ko se fa' li a). An order of Reptilia, comprising only one 

 living form, Sphenodon, of the New Zealand region. 



Rodent {ro' dent). A gnawing mammal, a member of the order Rodentia (rats, mice, 

 rabbits, squirrels, etc.). 



Rotation (ro ta' shun). The movement of the protoplasm of a cell in a continuous 

 path, often just within the cell wall. 



Rotifer (ro' tifer). An animal belonging to the small phylum Rotifera, of uncertain 

 position in the animal series. Sometimes called a wheel-animalcule from the 

 appearance of rotation given by a circle of ciUa at one end of the body. 



Rotifera (ro tif er a). A group of animals (the rotifers) usually regarded as a separate 

 phylum, but of uncertain position in the animal kingdom. For definition see 

 Chapter XII. 



Sacculina (sak' ku W na). A degenerate crustacean, related to the barnacles, parasitic 



on crabs. 

 Sacral {sa' kral). Pertaining to the sacrum, the region between the hips. 



Sacrum {sa' krum). A group of vertebrae, more or less fused, in the region between the 

 hips. 



Sagitta {sajif ta). A marine animal of small size, sometimes called the arrow-worm, 

 but not a true worm at all. Its relationship to other animals is obscure. 



Salientia (sa' li en' shi a). An order of Amphibia including the tailless forms (frogs, 

 toads). 



Saliva (sa li' va). The fluid secreted by the salivary glands about the mouth. 



Salivary (saVivari). Pertaining to sahva, the fluid secreted into the mouth in 

 mammals. 



Salvelinus fontinalis (sal' ve li' nus fon' ti na' lis). A species of trout. 



Sarcode (sar' kode). The term first applied to protoplasm by Felix Dujardin. 



Sarcolemma (sar' ko lem' ma). The membrane surrounding a striated muscle cell. 



Sarcoplasm (sar' ko plaz'm). The protoplasm of a striated muscle cell, as distin- 

 guished from the enclosed sarcostyles. 



Sarcostyle (sar' ko stile). One of the longitudinal fibrils or contractile elements of a 

 striated muscle cell. In it the light and dark bands characteristic of such muscle 

 are located. 



Scaphiopus (ska fi' o pus) . A genus of spade-foot toads. 



Scaphites (skaf i' teez). A genus of extinct cephalopods of the ammonitic form. 



Scaphopoda (skaf op' o da) . A class of Mollusca in which the shell and mantle are 

 tubular, as in Dentalium. 



Scapula (skap' u la). The shoulder blade; a bone of the pectoral girdle, located on or 

 near the dorsal side of the body. 



Schleicher, W. (shW Her). A German biologist. 



Schleiden, Matthias (shW den). German botanist, 1804-1881, to whom is often 

 attributed a share in the establishment of the cell-theory (see Schwann). 



Schneider, C. (shni' der). A German biologist. 



Schultze, Max (shooW sa). German biologist and anatomist, 1825-1874. 



Schwann, Theodor (shvahn). German physiologist and anatomist, founder of the cell- 

 theory. Lived 1810-1882. 



Sciuridse (si u' ri dee). The family of rodents including the flying-squirrels, squirrels, 

 marmots, and chipmunks. 



