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RIB 



Rhodosporeae, n; pliu, rod'o- 

 spdr f '$-e (Gr. rhodon, a rose ; 

 spora, seed), a Sub-order of Algae, 

 constituting rose or purple- 

 coloured sea-weeds, with fronds 

 formed of a single row of articul- 

 ated cells, or of several rows of 

 cells combined into a- flat expan- 

 sion. 



Rhodymenia, n., rod'-i-men'-i-a 

 (Gr. rhodon, a rose ; humen, a 

 thin membrane), a genus of sea 

 plants, Ord. Algae : Rhodymenia 

 palmata, pdl-mdt'a (L. palmdtus, 

 marked with the palm of the 

 hand), the sea - weed called 

 Dulse. 



rhomboid, n., rimf-boyd (L. rhom- 

 bus, Gr. rhombos, a magical 

 wheel ; eidos, resemblance), a 

 four-sided figure having its oppos- 

 ite sides equal, but its angles not 

 right angles : rhomboideus, n., 

 rdm-bdyd'e'US, the name of two 

 muscles,. * rhomboideus minor ' 

 and *r. major,' which are placed 

 parallel to one another, and are 

 separated only by a slight in- 

 terval ; the rhomb oidei extend 

 obliquely from the spinous pro- 

 cesses of the lowest cervical, and 

 some of the upper dorsal vertebrae, 

 to the base of the scapula. 



rhonchus, n., r&ngk'-tis (L. rhon- 

 chus, Gr. rhongchos, a snoring), a 

 wheezing, snoring, sibilant, chirp- 

 ing, or whistling sound, usually 

 low-toned, produced in the air 

 passages by the narrowing of their 

 calibre, heard on auscultation. 



Rhus, n., rus (Gr. rhousios, red- 

 dish-brown ; rhous, a tree whose 

 bark and fruit are used in tan- 

 ning), a genus of plants, Ord. 

 Anacardiaceae,. the fruit and 

 leaves of some species becoming 

 a reddish - brown in autumn : 

 Rhus toxicodendron, ttiks'-ik-o* 

 dend'-ron (L. toxicum, Gr. toxikon, 

 poison ; Gr. dendron, a tree), 

 Poison-oak, found in N. America, 

 leaves used in medicine as a stim- 

 ulant, and, like other species, 



yields an acrid milky juice : R. 

 radicans, rad-ik'anz (L.rddicans t 

 striking or taking root),. Poison- 

 ivy or Poison -vine : R! venenata, 

 vVMn-dt'-a (L> vZnendtus, fur- 

 nished with poison from vemn- 

 um, poison), Poison-sumach, or 

 Poison-elder, possesses acrid, pois- 

 onous properties : R. coriaria, 

 ktir'i'dr'-t'd (L. coridrius, belong- 

 ing to leather from corium, 

 leather); R. typhina, ftf-in'-a (Gr. 

 tuphe or tiphe, spelt or German 

 wheat); R. glabra, gldV-ra (L. 

 glaber, smooth, without hair), 

 are species which are extensively 

 used in tanning, and their fruit 

 is acid : R. cotinus, IcSt'-m-us (L. 

 cdtmus, a shrub yielding a purple 

 dye), called wig-tree inFrance, from 

 the hairy appearance of its abort- 

 ive pedicles, yields the yellow 

 dye-wood Toung Fustic : R. suc- 

 cedanea, sutf-sZd'dnfoa (L. snc- 

 ceddn$us, that supplies the place 

 of something), the species whose 

 fruit produce Japan-wax, imported 

 from that country : R. vernicif- 

 era, vern'-is-if'-er-a (L. verno, I 

 spring, I bloom ; fero, I bear), a 

 small Japanese tree, yielding the 

 famous lacquer so extensively 

 employed by the inhabitants of 

 that country. 



rhythm, n., rithm (Gr. rhuthmos, 

 measured motion), the harmony 

 and due relation which exists 

 between the different movements 

 of an organ in health: rhythmic, 

 a., rith'-mik, also rhythmical, a., 

 ritli'mik-al, denoting the regular 

 healthy discharge of the functions 

 of an organ, as- the pulsations of 

 the heart. 



rib, n., rib (Dut. ribbe, a rib, a 

 beam), in anat., one of the curved 

 bony hoops or bars of the thorax 

 which protect the lungs, the 

 heart, etc. ; in bot., the central 

 longitudinal nerve or vein of a 

 leaf: true ribs, the seven ribs 

 which are attached to the sternum 

 or breast, bone, as distinguished 



