402 



INDEX AND GLOSSARY 



ginella, 371 : Gymnosperms, 375 : Angio- 

 sperms, 381. 



Meg aspore (jj.eya.s, large : <riropd, a seed), 

 the female spore in plants with sexually 

 dimorphic spores, al-ways distinguished 

 by its large size from the male or micro- 

 spore : Salvinia, 368: Selaginella, 371 : 

 Gymnosperms, 375 : Angiosperms, 382 



Megazo'oid (/At'ya? large : ro>oi/, animal : 

 eldos, form), the larger zooid in unicel- 

 lular organisms with dimorphic zooids, 

 35> 132 



Mer istem. (/u.epumj|u.a, formed from 

 /aepujou, to divide), indifferent tissue of 

 plants from which permanent tissues are 

 differentiated, 350 



Mes'entery (ju.e'<ros, middle : evrepov, in- 

 testine), a membrane connecting the en- 

 teric canal with the body-wall, 279 : de- 

 velopment of, 302 



Mes'oderm (/meo-os, middle : Sepfia, skin), 

 the middle cell-layer of triploblastic 

 animals : Polygordius, 278 . develop- 

 ment of, 299: splitting of to form somatic 

 and splanchnic layers, 302 



Mesoglce'a (ju.eVos, middle : y\oia, glue), 

 a^transparent layer between the ecto- and 

 endo-derm of Coelenterates : in Hydra, 

 225 : in Bougainvillea, 244 



Mes'ophyll (ju,e'pos, middle : <j>v\\ov, a 

 leai), the parenchyma of leaves, 352 



Mes'ostates (ju,e'cro?, middle : trrrfvai, to 

 stand), intermediate products formed 

 during metabolism (q.v.) and divisible 

 into (a) anabolic mesostates or ana- 

 states, products formed during the con- 

 version of food-materials into proto- 

 plasm ; and (b) katabolic mesostates 

 or katastates, products formed during 

 the breaking down of protoplasm, 18 



Metab'olism Oxera/SoArj, a change), the 

 entire series of processes connected with 

 the manufacture of protoplasm, and 

 divisible into (a.) constructive meta- 

 bolism or anabolism, the processes by 

 which the substances taken as food are 

 converted into protoplasm, and (b) de- 

 structive metabolism or katabolism, 

 the processes by which the protoplasm 

 breaks down into simpler products, ex- 

 cretory or plastic, 17 



Met'amere (/u.eYa, after : /mepos, a part), a 

 body-segment in a transversely seg- 

 mented animal such as Polygordius, 271, 

 273 : development of, 301 : limited num- 

 ber and concrescence of in Crayfish, '314 



Metamorphosis (/mtTa^op^oxris), a trans- 

 formation applied to the striking change 

 of form undergone by certain organisms 

 in the course of development after the 

 commencement of free existeuce : Vor- 

 ticella, 133 : Polygordius, 306 



Mic robe (/ui/cpos, small : /Si'os, life). See 



MICROCOC'CUS (jai/cpos, small : KOKKOS, 

 a berry) (Figure), 86 



Mlcrogam'ete (/uuxpos, small : -ya^e'cu, to 

 marry), a male gamete (g.v.), distin- 

 guished by its smaller size from the 

 female or megagamete, 132 



Micro-millimetre, the one-thousandth of 

 a millimetre, or i-25,oooth of an inch, 84 



Micro-organism. See Bacteria. 



Micronucleus ( juu*p6s, small : micleits, a 

 kernel), in, 128 



Micropyle (jul/cpoj, small : irvArj, an en- 

 trance), 375 



Micro-sporan'giumGu/cpos, small : <rnopd, 

 a seed : dyyeiov, a vessel), the male 

 sporangium in plants with sexually di- 

 morphic sporangia, usually distinguished 

 by its smaller size from the female or 

 mega-sporangium : Salvinia, 368 : Se- 

 laginella, 371 : Gymnosperms, 376 : An- 

 giosperms, 381 



Mic'rospore (juuKpo?, small t OTropa, a 

 seed), the male spore in plants with 

 sexually dimorphic spores, always dis- 

 tinguished by its small size from the 

 female or mega-spore : Salvinia, 368 : 

 Selaginella, 371 : Gymnosperms, 376 : 

 Angiosperms. 381 



Microzo'oid (jul^po?, small : ^Voov, an ani- 

 mal : clSo?, form), the smaller zooid in 

 unicellalar organisms with dimorphic 

 zooids, 35, 132 



Midrib of leaf, Moss, 335 



Minimum temperature for amoeboid move- 

 ments, 21 



Mollusca, the, 309 



Monoecious (/uoyo?, single : OIKOS, a 

 house), applied to organisms in which 

 the male and female organs occur in the 

 same individual, 199, 234 



Monopod'ial (/xo^os, single : TTOVS, a foot), 

 applied to branching in which the main 

 axis continues to grow in a straight line 

 and sends off secondary axes to the 

 sides. 138 



MONOSTROMA (/xdvos, single : o-rpw/xa, 

 anything spread out), 202 (Figure) 



Morphol'Ogy (juop^, form : Adyos a dis- 

 cussion), the department of biology 

 which treats of form and structure, 9 



Mor'ula (diminutive of vionnn, a mul- 

 berry) See Polyplast. 



MOSSES : Figures, 333, 338 : general 

 characters, 332 : structure of stem, 334 : 

 leaf, 335 : rhizoids, 335 : terminal bud, 

 335 1 reproduction, 336 : development 

 of sporogonium, 337 : of leafy plant, 

 339, 340 : alternation of generations, 

 340 : nutrition, 340, 341 



Mouth : Kuglena, 47 : Paramoccium, no: 

 Hydra, 223 : Medusa, 241 : Polygordius, 

 271: backward shifting of in Crayfish, 



MUCOR (mncor, mould) '.Figure, 159: 



