RHI- 



276 



RIN- 



the basal granule with the nucleus 

 in certain Protozoa (zool.). 



rhizotaxis (n'zotak'sis) n. [Gk. rhiza, 

 root ; taxis, arrangement.] Root 

 arrangement (bot.). 



rhodophane (ro'dofan) n. [Gk. rhodon, 

 rose ',phainein, to show.] Chromo- 

 phane ; the red oil globule found 

 in the retina of Marsupials, Birds, 

 Reptiles, Fishes (pftys.). 



rhodophyll (ro'dofil) n. [Gk. rhodon, 

 rose ; phyllon, a leaf.] The red 

 colouring matter of red Algae (dot.). 



rhodopsin (rodop'sin) n. [Gk. rhodon, 

 rose ; opsis, sight.] A temporary 

 reddish - purple pigment in the 

 retinal rods ; visual purple (phys.). 



rhombencephalon (romb'enkef'alon, 

 -seT-) n. [Gk. rhombos, magic 

 wheel ; engkephalon, brain.] The 

 hind-brain. 



rhombic (rom'bik) a. [Gk. rhombos, 

 magic wheel.] Appl. lip and 

 grooves of brain at the rhomboid 

 fossa (emb.). 



rhombogen (rom'bojen) n. [Gk. 

 rhombos, magic wheel ; genos, off- 

 spring.] A phase of the parent 

 form in the life cycle of some 

 Mesozoa (zool.). 



rhomboid (rom'boid) a. [Gk. rhom- 

 bos, magic wheel ; eidos, form.] 

 Rhombus-shaped ; appl. fossa, sinus, 

 ligament (anat.). 



rhomboideus, major and minor, 

 parallel muscles connecting the 

 scapula with the spinal column 

 (anat.). 



rhomboid - ovate, something be- 

 tween rhomboid and oval in shape. 



rhopalium (ropa'lTum) . [Gk. 

 rhopalon, a club.] A marginal 

 sense organ of Discomedusae 

 (zool.). 



rhynchocoel (ring'kosel) . [Gk. 

 rhyngchos, snout ; koilos, hollow.] 

 In Nemertines, the cavity whose 

 contracting muscular walls evert 

 the proboscis (zool.}. 



rhy nchodaeum (ring'kode'um) n. [Gk. 

 rhyngchos, snout ; odaios, pert, a 

 way.] The precerebral region of a 

 Nemertine (zool.). 



rhynchodont (ring'kodont) a. [Gk. 

 rhyngchos, snout ; odous, tooth.] 

 With a toothed beak (zool.). 



rhynchophorous (ringkof'orus) a. 



[Gk. rhyngchos, beak ; pherein, to 

 bear.] Beaked. 



rhynchostome (ring'kostom) n. [Gk. 

 rhyngchos, snout ; stoma, mouth.] 

 The anterior terminal pore of 

 Nemertines through which the pro- 

 boscis is everted (zool.). 



rhythm (rithm) n. [Gk. rhythmos, 

 measured motion.] Regularity of 

 movement, as seen in heart pulsa- 

 tion (phys.), or movement of tele- 

 graph plant leaves (bot.). 



rib (rib) n. [A.S. ribb, a rib.] One 

 of the curved bones of the thorax 

 articulating with the spine and 

 either free at the other end or 

 connected with the sternum (anat., 

 zool.) ; the central vein of a leaf 

 (hot.). 



rictal (rik'tal) a. [L. rictus, mouth 

 aperture.] Pert, the mouth gape 

 of a Bird. 



rigor (rtg'or) n. [L. rigor, stiffness.] 

 The rigid state of plants when they 

 are not sensitive to stimuli (bot.) ; 

 a state of rigidity. 



rigor mortis, the stiffening of the 

 body after death, due to myosin- 

 formation, and lasting till the 

 commencement of decomposition 

 (biol.). 



rima (rl'ma) n. [L. rima, a cleft.] 

 A cleft or fissure (anat.}. 



rimate (ri'mat) a. [L. rima, a cleft.] 

 Having fissures. 



rimiform (rfmiform) a. [L. rima, 

 a cleft ; forma, shape.] In the 

 shape of a narrow fissure. 



rimose (rfmos) a. [L. rima, a cleft.] 

 Having many clefts or fissures. 



rimulose (rlm'ulos) a. [L. rimula, 

 a small cleft.] Having many small 

 clefts. 



rind (rind) n. [A.S. rinde, bark of a 

 tree.] The outer skin or cortex 

 (bot.). 



ring canal, a circular canal running 

 close to and parallel with the 

 umbrella margin in Hydrozoa 

 (zool.). 



ring cell, a thick-walled cell of the 

 sporangium annulus of Ferns (bot.). 



ring vessel, a structure in the head 

 of Cestodes which unites the four 

 longitudinal excretory trunks (sool.). 



ringed bark, the bark of a tree 

 where the formations of phellogen 



