USED IN NATURAL HISTORV. 



120 



or delivered by a saw, in its pas- 

 sage through any substance, may, 

 perhaps, be thus designated. 



RI'MA. Lat. A fissure. The in- 

 terstice between the valves of a 

 shell when the hymen is removed. 



RIMO'SE. Fissured, or irregularly 

 cracked, like the bark of a tree. 



R ix GENT. fr. hit. rmgo, to grin. In 

 botany, applied to certain corollas, 

 the petals of which cohere into 

 the form of a mouth, which gapes 

 on pressing the sides. 



RIPPLE-MAIIKS. In geology, the un- 

 dulations which occur on the sur- 

 face of many rocks, resembling 

 the ridges and indentations left 

 on mud and sand by small waves 

 of water. They are most distinct 

 on surfaces where a change of 

 deposit has taken place, as where 

 sandstones alternate with thin 

 clay partings. 



RO'BUK. Lat. An oak ; strength. 



ROCK. Any mineral aggregate, whe- 

 ther hard or soft; the term there- 

 fore includes sand, marble, clay, 

 granite, &c. 



ROCK CRYSTAL. A pure crystallized 

 variety of quartz. 



ROCK-SALT. Common salt found in 

 masses or beds in the new red 

 sandstone. 



RODE'NTIA. fr. lat. rodere, to gnaw. 

 An order of mammals. 



RODENTS. Gnawers; animals of 

 the order of rodentia. 



ROITELET. Fr. Dimin. of rot, a 

 king. A wren. 



ROLLED FLINTS. Pebbles, (p. 129, 

 Book viii). 



ROOTING. In botany, sending out 

 lateral roots. 



ROU'Q.UAL. A kind of whalebone 

 whale. 



ROSA'CEJE. Name of a family of 

 plants, which includes the rose. 



ROSE'OUS. Rose-coloured. 



Rosso'us. The Sun-dew, or Dro- 

 sera. 



HOSTEL. In botany, the pointed 

 part of the embryo which tends 

 6* 



downward at the first germina- 

 tion of the seed. 



ROSTELLA'RIA. fr. lat. rostellum, a 

 little beak. A genus of univalvo 

 mollusks. (p. 85, Book viii). 



ROS'TRATE. Furnished with a 



beak. 



ROS'THUM. Lat. A beak. The ex- 

 tension of that part of the shell 

 in which the canal is situated. In 

 botany, any rigid prolongation of 

 considerable length. 



RO'SULATK. fr. lat. rosa, a rose. In 

 botany, applied to parts which 

 are not opposite, but which never- 

 theless become apparently so by 

 the contraction of the joints of the 

 stem, and lie packed closely over 

 one another, like the petals of a 

 double rose. 



ROTA'TA. Lat. Rotate; wheel 



shaped. 



RO'TATE. Wheel-shaped. Applied 

 to a monopetalous corolla, when 

 the limb is flat, and the tube very 

 short. 



ROTA'TIOST. In botany, a special 

 motion of the sap, observed in 

 plants of low organization. It 

 consists of a special circulation 01" 

 the fluid contained in the interior 

 of each cell, the rotation in one 

 cell never interfering with that 

 in another cell. 



ROTA'TOR. fr. lat. ro/a, a wheel. A 

 name given to muscles, which 

 turn the parts to which they aro 

 attached on their axes. 



ROTATO'RIA. Lat. Rotatory. 



ROTHE-TODTE-LIEGENDE. Ger. NeW 



red sandstone. (Note, p. 47, Book 

 viii). 



ROTHOMAGK'NSIS. Lat. from rotho- 

 ma'gum, a temple of Roth, a di- 

 vinity of that part of Gaul, now 

 called Normandy; hence too the 

 name of the city Rouen. Belong- 

 ing or relating to Rouen. Specific 

 name of an ammonite. 



RO'TULA. The patella. 



ROTU'JTD. Round, circular, spLcri 

 cal. 



I 



