prevernal 



Procambium 



come) Buds, dormant eyes, pre- 

 sent on any given portion of the 

 stem, which produce epicormic 

 branches (Hartig). 



prever'nal (pre, before, rernalis, of 

 the spring), early spring flowering. 



Prickle, outgrowths of the rind or 

 bark, as those of the rose ; prickly, 

 armed with prickles. 



pri'mary, prima'rius (L&t. , chief), (1) 

 used of the part first developed ; 

 (2) the main divisions of a leaf or 

 umbel ; ~ Ax'is, the main stem ; 

 ~ Bast, consists of sieve tissues 

 and parenchyma ; ~ Cor'tex, the 

 PEBIBLEM ; ~ Des'mogen, = PRO- 

 CAMBIUM ; ~ Lamella, of a spore, 

 is the outermost layer of its coats, 

 representing the original wall ; 

 ~ Leaves, the primordial leaves ; 

 ~ Lay'er, see ' ' tapetal cell " (infra) ; 

 ~Mem'brane, the first (?) cell-wall ; 

 ~ Mem'bers, the primary shoot 

 and root ; ~ Mer'istem, the embry- 

 onic tissue of a young organ ; ~ 

 Pet'iole, the main rhachis of a com- 

 pound leaf ; ~ Phlo'em = BAST ; 

 ~ Root, the main root developed 

 from the radicle ; ~ Shoot, the main 

 stem developed from the plumule ; 

 ~ Struc'ture, a nascent organ, as of 

 root or shoot ; ~ tape'tal Cell, or 

 Lay'er, the source whence the tape- 

 turn is formed by bipartition of a 

 cell or layer of periblem ; the other 

 part of the division becoming the 

 archesporium ; ~ Tis'sue, (a) that 

 first formed or (b*) formed during 

 the first season's growth ; ~ Wood, 

 the wood developed by the pro- 

 cambium. 



primigen'ius (Lat., first produced) = 

 PRIMITIVDS.. 



Pri'mine, Pri'mina (primus, first), the 

 outer integument of an ovule. 



primitive, primiti'vm (Lat., first 

 of its kind), applied to the part 

 first developed ; specific types, 

 in contrast to varieties and hy- 

 brids ; ~ Wall, a boundary between 

 the ooplasm and periplasm of the 

 oosphere in Cystopus Bliti, De 

 Bary (Stevens). 



208 



Primor'dia, pi. of Primor'dium (Lat., 

 the beginning), a member or organ 

 in its earliest condition ; the Ger- 

 man " Anlage" ; primor'dial, pri- 

 mordia'lis, first in order of appear- 

 ance ; ~ Cell, a naked cell, one 

 without a cell-wall ; <~ Epider'mis, 

 the epidermis when first formed ; 

 ~Leaf, an intermediate form be- 

 tween the cotyledon and those of 

 the adult plant produced by growth 

 from the plumule ; ~ Tis'sue, 

 ground tissue ; ~ U'tricle, the outer 

 layer of cell-protoplasm lining the 

 inner surface of a vacuolated cell ; 

 by some considered the same as 

 ECTOPLASM. 



Pri'mospore (primus, first, <nropa, a 

 seed), term proposed by C. Mac- 

 millan for those cases in which the 

 spore is but little differentiated 

 from an ordinary cell of the parent 

 organism. 



prismatic, prismat'icus (Lat., like a 

 prism), prism-shaped, with flat faces 

 separated by angles ; Prismench'- 

 yma (Zyxv/J.a, an infusion), pris- 

 matic cellular tissue. 



Pris'on-Flow'ers, those which imprison 

 their insect-visitors until fertiliza- 

 tion is effected. 



Proan'giosperms (pro, for, + Angios- 

 perm), an Angiosperm in the act of 

 becoming so from some ancestral 

 form (Saporta and Marion ) ; Pro- 

 angiosper'my, the state in question. 



Proanthe'sis (vrp^), early, a.V0?7<m, 

 flowering), flowering in advance of 

 the normal period, as some flowers 

 appearing in autumn in advance of 

 the ensuing spring (Pax). 



Probas'id (pro, for, + BASIDIUM), Van 

 Tieghem's term for an organ inter- 

 mediate between a basidium and a 

 sporophore in Basidiomycetes, bear- 

 ing a teleutospore. 



proboscid'eus (proboscis, a snout), 

 having a large terminal horn, as 

 the fruit of Marfynia. 



Procam'bium (pro, for, + CAMBIUM), 

 the embryonic tissue, consisting of 

 somewhat elongated cells, from 

 which the vascular tissue is eventu- 



