ECH- 



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echinopluteus (eVinoploo'teus, e'kl'no- 

 ploo'teus) n. [Gk. echinos, spine ; 

 L. pluteus, shed.] The larva or 

 pluteus of echinoids, from its sup- 

 posed resemblance to an upturned 

 easel (zool.). 



echinulate (6kin'ulat) a. [Gk. echinos, 

 spine.] Having small spines (zool.). 



ecology (ekol'qji) n. [Gk. oikos, house ; 

 logos, discourse.] That part of 

 biology which deals with the re- 

 lationship between organisms and 

 their surroundings (biol.). 



ectental (gktgn'tal) line, the line 

 where the ectoderm and endoderm 

 meet at the blastopore of a gastrula 

 (cyt.). 



ectethmoid (ekteth'moid) n. [Gk. 

 ektos, without ; ethmos, sieve ; eidos, 

 resemblance.] The lateral ethmoid 

 bone (anat.). 



ecthoraeum (ek'thore'um) n. [Gk. 

 ekthroskein, to leap out.] The 

 thread of a nematocyst (zool.}. 



ectoblast (ek'toblast) n. [Gk. ektos, 

 without ; blastos, bud.] See epi- 

 blast. 



ectobronchium (ek'tobrong'kium) n. 

 [Gk. ektos, without ; brongchos, wind- 

 pipe.] See ectobronchus. 



ectobronchus (ek'tobrong'kus) n. [Gk. 

 ektos, without ; brongchos, wind- 

 pipe.] A lateral branch of the 

 main bronchus in birds (zool.). 



ectocarpous (ek'tokar'pus) a. [Gk. 

 ektos, without; karpos, fruit.] Having 

 the gonads of ectodermal origin 

 (zool?). 



ectochondrostosis (ek'tdkondrosto'sis) 

 n. [Gk. ektos, without ; chondros, 

 cartilage ; osteon, bone.] The de- 

 position of lime-salts beginning in 

 the perichondrium and gradually 

 invading the cartilage (anat.). 



ectochone (ek'tokon) n. [Gk. ektio, 

 without ; choane, funnel.] A funnel- 

 shaped chamber into which the 

 ostia in certain Sponges lead (sool.). 



ectocoelic (eYtose'lik) a. [Gk. ektos, 

 outside ; koilos, hollow.] Pert. 

 structures situated outside the 

 enteron of the Coelenterates (zool.). 



ectocondyle (elc'tdkon'dil) n. {Gk. 

 ektos, outside ; kondylos, knob.] 

 The outer condyle of a bone 

 (anat.). 



ectocranial (eYtokra'nial) a. [Gk. 



ektos, outside ; kranton, skull.] 

 Pert, outside of skull (anat.). 



ectocuneiform (gk'tokune'iform) n. 

 [Gk. ektos, outside ; L. cuneus, 

 wedge ; forma, shape.] A bone in 

 the distal row of the tarsus (anat.). 



ectocyst (ek'toslst) n. [Gk. ektos, 

 outside ; kystis, bladder.] The 

 outer layer of the zoecial wall in 

 Polyzoa (zool.). 



ectoderm (eYtddgrm) n. [Gk. ektos, 

 outside ; derma, skin.] The outer 

 layer of a multicellular animal, 

 when composed of cells (zool.) ; 

 the epidermis in higher mammals 

 (anatj. 



ectogenous (ektoj'e'nus) a. [Gk. ektos, 

 outside ; gignesthai, to produce.] 

 Able to live an independent life ; 

 appl. Bacteria (dot.). 



ectoglla (ektog'lia) n. [Gk. ektos, 

 outside ; glia, glue.] An outer 

 layer of cells in the central 

 nervous system (anat.). 



ectolecithal (6k'tol6s'ithal) a. [Gk. 

 ektos, outside ; lekithos, yolk of an 

 egg.] Having the yolk surround- 

 ing the formative protoplasm 

 (zool.). 



ectoloph (gk'tolof) n. [Gk. ektos, 

 outside ; lophos, crest.] The ridge 

 stretching from the paracone to 

 the metacone in a lophodont molar 

 (anat.). 



ectomere (ek'tomer) n. [Gk. ektos, 

 outside ; meros, part.] An epiblast 

 cell which gives rise to ectoderm 

 (cyt.). 



ectoparasite (eYtopar'asit) n. [Gk. 

 ektos, outside ; para, beside ; sttos, 

 food.] A parasite that lives on 

 the exterior of an organism (zool.). 



ectopatagium (ek'topata'jium) . 

 [Gk. ektos, outside ; L. patagium, 

 border.] The part of the wing- 

 like membrane of bats carried on 

 the metacarpals and the phalanges 

 (zool.). 



ectophyte (eVtoflt) n. [Gk. ektos, 

 outside ; phyton, plant.] Name 

 given to an external parasite in 

 the plant world (bot.). 



ectoplasm (Sk'to'plazm) n. [Gk. 

 ektos, outside ; plasma, something 

 moulded.] The external layer of 

 protoplasm in a cell, usually slightly 

 modified (diol.) ; the ectosarc in a 



