MER- 



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MER- 



part ; sporos, seed.] A segment or 

 spore of a multicellular spore-body 

 (bot.). 



meristele (mer'istel) n. [Gk. meros, 

 part ; stele, pillar.] A separate 

 part of a monostelic stem passing 

 outwards from stele to leaves ; the 

 branch of a stele supplying a leaf 



meristem (meYistgrn) n. [Gk. 

 meristes, a divider.] Tissue formed 

 of cells all capable of division, as 

 found at growing points ; meris- 

 matic or meristematic tissue (bot.}. 



merlstematic (mgr'istemat'Ik) a. [Gk. 

 meristes, a divider.] Pert, or con- 

 sisting of meristem ; appl. tissue, 

 cells of growing point ; merismatic 

 (bot.). 



meristic (mSris'tik) a. [Gk. meristes, 

 a divider.] Segmented ; divided 

 off into parts (bot.). 



meristic variation, changes in the 

 number of parts or segments, and 

 in the geometrical relations of the 

 parts ; cf. substantive variation 

 (biol.). 



meristogenetic (me'ris'tqje'ne't'ik) a. 

 [Gk. meristes, a divider ; genesis, 

 descent.] Developing from mer- 

 istem (bot.). 



merithallus (me'rlthal'us) n. [Gk. 

 meros, part ; thallos, young shoot.] 

 An internode (bot.). 



mermaid's purse, the horny floating 

 or fixed egg-envelope of skates and 

 sharks (zool.). 



meroblastic (mer'oblas'tik) a. [Gk. 

 meros, part ; blastos, bud.] Appl. 

 ova which undergo only partial 

 segmentation or cleavage in de- 

 velopment (zool.) ; developing from 

 part of the opsphere only (bot.). 



merocerite (meros'e'rlt) n. [Gk. meros, 

 thigh ; keras, horn.] The fourth 

 segment of crustacean antennae 

 (zool.). 



merocyte (mer'oslt) n. [Gk. meros, 

 part ; kytos, hollow.] A nucleus 

 lying in the yolk, directly below 

 the blastoderm in a meroblastic 

 ovum (cyt.). 



merogastrula (mer'ogaVtroola) n. 

 [Gk. meros, part ; dim. of gaster, 

 stomach.] The gastrula formed 

 from a meroblastic ovum (zool.). 



m orogenesis (meVoje'n'e'sis) n. [Gk. 



meros, part ; gigncsthai, to produce.] 

 Formation of parts ; segmentation. 



merognathite (meVognath'it) n. [Gk. 

 meros, thigh ; gnathos, jaw.] The 

 fourth segment of a crustacean 

 mouth-part (zool.). 



merogony (merog'onT) n. [Gk. meros, 

 part ; gone, generation.] Develop- 

 ment of normal young of small size, 

 from part of an egg, in which there 

 was no female pronucleus (zool). 



meroistic (meYois'tlk) a. [Gk. meros, 

 part.] Appl. certain insect ovaries 

 which produce vitelligenous cells 

 in addition to ova (zool.). 



meromorphosis (mer / 6m6r'f6s!s) n. 

 [Gk. meros, part ; morphosis, change.] 

 Regeneration of a part when the 

 new part is less than that lost 

 (zool.). 



meront (mSront') n. [Gk. meros, 

 part ; ons, being.] A uninucleate 

 schizont-stage in Neosporidia suc- 

 ceeding the planont-stage, which 

 multiplies by fission (zool.). 



meroplankton (mer'oplang'kton) n. 

 [Gk. meros, part ; plangktos, 

 wandering.] Plankton living only 

 part-time near the surface (bot., 

 zool.). 



meropodite (merop'odit') n. [Gk. 

 meros, thigh ; pous, foot.] The 

 fourth segment of a thoracic ap- 

 pendage in the Crustacea (zool.). 



meros (me'rfis) n. [Gk. meros, thigh.] 

 The fourth segment of a crustacean 

 appendage (zool.). 



merosomatous (meVosom'atus) a. 

 [Gk. meros, part ; soma, body.] 

 Appl. ascidiozooids divided into 

 two regions, thorax and abdomen 

 (zool). 



merosome (mer'osom) n. [Gk. meros, 

 part ; soma, body.] A body seg- 

 ment, somite, or metamere (zool.). 



merosthenic (me'rosthe'n'ik) a. [Gk. 

 meros, thigh ; sthenos, strength.] 

 With unusually developed hind- 

 limbs (zool.). 



merotomy (merot'dmi) n. [Gk. meros, 

 part ; temnein, to cut.] Segmenta- 

 tion or division into parts (zool.). 



merozoite (mer'ozo'it) n. [Gk. meros, 

 part ; zoon, animal.] A cell, the 

 division-product of a schizont in 

 Sporozoa (zool.). 



merozoon (mer'6zo'8n) n. [Gk. meros, 



