HYD- 



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HYD- 



hydathode (hl'dathod) n. [Gk. hydor, 

 water ; odos, way.] An epidermal 

 structure specialized for the secre- 

 tion of water (bof.). 



hydatid (hl'datid) n. [Gk. hydatis, 

 watery vesicle.] Any vesicle or 

 sac filled with a clear watery-like 

 fluid, and containing encysted 

 stages of the larval tapeworms 

 (zool.). 



hydatiform (hldat'ff6rm) a. [Gk. 

 hydatis, watery vesicle ; L. forma, 

 shape.] Resembling a hydatid 

 (zool.). 



hydatigenous (hi'datlj'gnus) a. [Gk. 

 hydatis, watery vesicle ; gignesthai, 

 to produce.] Producing or forming 

 hydatids (zool.). 



hydranth (hl'dranth) n. [Gk. hydor, 

 water ; anthos, flower.] A nutri- 

 tive zooid in a hydroid colony 

 (zool.). 



hydrocaulis (hi'drok61'is) n. [Gk. 

 hydor, water ; kaulos, stalk.] The 

 branching vertical portion of the 

 coenosarc in a hydroid colony 

 (zool.). 



hydrocircus (hl'droseVkus) n. [Gk. 

 hydor, water ; kirkos, circle.] The 

 hydrocoelic ring surrounding the 

 mouth in Echinoderms (zool.). 



hydrocladia (hl'droklad'ia) n. plu. 

 [Gk. hydor, water ; klados, short.] 

 The secondary branches of a 

 hydrocaulis (zool.). 



hydrocoel (hi'drosel) n. [Gk. hydor, 

 water ; koilos, hollow.] The water- 

 vascular system in the Echino- 

 derms (zool.). 



hydrocyst (hfdrosist) n. [Gk. hydor, 

 water ; kystis, bladder.] A dactylo- 

 zooid (zool). 



hydroecium (hldre'shium) n. [Gk. 

 hydor, water ; oikos, house.] A 

 closed tube at the upper end of a 

 Siphonophore ; an infundibulum 

 (zool.). 



hydroid (hl'droid) n., a. [Gk. hydor, 

 water ; eidos, resemblance.] A 

 tracheid (tot.) ; pert, or similar to 

 the genus hydra ; the polyp form 

 of a Hydrozoan (zool.). 



hydrolysis (hldrol'isis) n. [Gk. hydor, 

 water ; lyein, to dissolve.] De- 

 composition of a chemical com- 

 pound by the addition of water 

 (phys.). 



hydrome (hi'drom) n. [Gk. hydor, 

 water ; mestos, full.] Any tissue 

 that conducts water (6ot.). 



hydromegatherm (hl'dromSg'a.thgrm) 

 n. [Gk. hydor, water ; mega, 

 great ; therme, heat.] A plant 

 which must have both moisture 

 and heat to develop fully (dot.}. 



hydrophilous (hldrof'ilus) a. [Gk. 

 hydor, water ; philein, to love.] 

 Pollinated through the agency of 

 water (dot.). 



hydrophyllium (hl'drofil'ium) n. [Gk. 

 hydor, water ; phyllon, leaf.] One 

 of leaf-like transparent bodies 

 arising above and partly covering 

 the sporosacs in a Siphonophore 

 (zool.). 



hydrophyte (hfdroflt) n. [Gk. hydor, 

 water ; phyton, plant.] An aquatic 

 plant. 



hydrophyton (hidrof'iton) n. [Gk. 

 hydor, water ; phyton, plant.] A 

 complete hydroid colony, root- 

 like organ, stem and branches 



v (zool.). 



hydroplanula (hi'droplan'ula) n. [Gk. 

 hydor, water ; L. planus, flat. J A 

 stage in the larval history of a 

 Coelenterate between a planula and 

 an actinula (zool.). 



hydropolyp (hl'dropol'ip) n. [Gk. 

 hydor, water ; F. polype, polyp.] 

 A polyp of a hydroid colony ; a 

 hydrula (zool.). 



hydropore (hl'dropor) n. [Gk. hydor, 

 water \poros, opening.] The open- 

 ing into the right hydrocoel in the 

 echinoderm larvae (zool.). 



hydrorhiza (hl'drorl'za) n. [Gk. hydor, 

 water ; rhiza, root.] The creeping 

 root-like portion of the coenosarc 

 of a hydroid colony (zool.). 



hydrosome (hl'drosom) n. [Gk. hydor, 

 water ; soma, body.] The con- 

 spicuously hydra-like stage in a 

 coelenterate life-history (zool.). 



hydrospire (hl'drdspir) n. [Gk. hydor, 

 water ; L. spira, coil.] The folds 

 on the stereom of blastoids ; re- 

 spiratory structures (pal.). 



hydrostome (hl'drostom) n. [Gk. 

 hydor, water ; stoma, mouth.] The 

 mouth of a hydroid polyp (zool.). 



hydrotaxis (hi'drotak'sis) n. [Gk. 

 hydor, water ; taxis, arrangement.] 

 The response of certain small 



