726 PHARMACEUTICAL BOTANY 
MEeEr’1cArP.—One of the two inferior akenes which are found with the carpophore 
making up the cremocarp in Umbellifere. 
MER’IsTEM.—Formative or undifferentiated tissue consisting of cells which in the 
living plant are in an active state of division. 
MERISTEMAT’Ic.— Consisting of generative cells or meristem. 
Mes’ocArp.—The middle region of the fruit wall or pericarp, lying between the 
epicarp and endocarp. 
Mes’opHyL_.—The region of leaf parenchyma within the epidermis or, in flat leaves, 
between the two epidermises. 
Mes’tome.—The conducting portion of a fibrovascular bundle. 
Metap’o.isM.—The sum total of all the chemical changes which take place in a 
living plant. 
METAGEN’EsIS.—Alternation of generations. The production of sexual indi- 
viduals by asexual means and asexual or neutral individuals by sexual means. 
MEeETAmMoR’PHOsIs.—A change in the form or function of an organ or organism. 
METAPHLO’EM.—Phloem formed by the cambium. Secondary phloem. 
METAXy’LEM.—The secondary xylem, formed by the cambium on its inner face. 
Micro.—A prefix of Greek origin meaning small. 
Mr’crosE.—A minute vegetable or animal organism, 
Mr’crocrys’TAts (Sphenoidal Crystals)—Very minute, arrowhead- or deltoid- 
shaped crystals frequently packed in great numbers in a single cell. 
Mr’cropyLe.—The opening between the coats of an ovule through which the pollen 
tube enters. The orifice or foramen in the seed coat through which the hypo- 
cotyl passes during germination. 
Microso’mes.—Applied by Strasburger to minute particles in the protoplasm which 
have a high degree of refringency. 
Microso’rus.—A lobe of the anther. 
MicrosPporANn’ciIuM.—A spore case containing microspores. An anther sac. 
Mi’crosporE.—A small spore found in a microsporangium. The pollen grain of 
a seed plant. 
Microspo’RoPHYLL.—A leaf bearing microsporangia. The stamen of seed plants. 
Mi'pie Lamev’tA.—A layer of calcium pectate or of some other base in com- 
bination with pectic acid, appearing within the vacuole between two plasma 
membranes during the last stage of cell division and appearing in suitably 
mounted matured tissues as a dividing line between the cellulose walls of 
adjacent protoplasts. 
Miw’r1s.—The large main central vein of a pinnately-veined leaf which is con- 
tinuous with the leaf stalk. 
Mrro’sis.—Indirect nuclear division. 
MonapDEL’PHOUs.—Applied to stamens which are united by their filaments into one 
set, as in the Malvacee. 
Monan’prous.—Possessing only one stamen. 
Monan’tHous.—Having only a single flower on the peduncle. 
Moni’trorM.—Resembling a chain of beads. 
Mono.—A prefix of Greek origin, meaning one or single. 
Monocar’PELLARY.—Of one carpel. 
Monocu.Amyp’£ous.—Possessing but one perianth whorl. 
Monocuin’ic Prisms (Monoclinic Crystals) .—Crystals possessing three axes of 
unequal length, two of which are obliquely inclined to each other and the 
third forming right angles to these two. 
