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GLOSSARY 



DiADELPHOus, (of stamcns) arranged or 

 combined into two sets. 



DiARCH, (of root) a stele with two pro- 

 toxylem groups. 



DicHOTOMOus, forking regularly by 

 pairs. 



Dicotyledonous, having two cotyle- 

 dons. 



DicTYOsTELE, a vasculat cylinder or 

 stele consisting of distinct bundles; a 

 dissected siphonostele. 



Digitate, (of leaves) with the leaflets 

 arising at the apex of the petiole. 



Dimerous, having all the parts in twos. 



Dioecious, with staminate and carpel- 

 late flowers on separate plants. 



Distichous, in two vertical ranks, as the 

 leaves of grasses. 



Dorsal, relating to the back or outer 

 surface of an organ. 



Drupe, a fruit developed from a single 

 carpel with a fleshy exocarp and a 

 hard stony endocarp or pit usually 

 containing a single seed. Less ex- 

 actly applied to stone fruits that are 

 multi-carpellate with one to several 

 seeds. 



Duct, an elongated cell or a multi- 

 cellular cavity; a gland. 



Ectophloic siphonostele, a stele in 

 which there is a zone of phloem out- 

 side the xylem but no inner phloem. 



Embryo, a rudimentary plant. 



Emergence, a surface outgrowth arising 

 from a few superficial layers, i.e., 

 prickles. 



Endarch, applied to primary xylem in 

 which the progressive development 

 of the elements is centrifugal. 



Endocarp, the inner layer of the peri- 

 carp or fruit coat. 



Endodermis, the innermost layer of the 

 cortex which abuts the stele. 



Endogenous, produced within from 

 deep-seated tissues instead of from 

 superficial layers. 



Endosperm, the nutritive tissue occur- 

 ring within the seed which is de- 

 rived from the triploid endosperm 

 nucleus. 



Endothecium, inner lining of the locule 

 of an anther. 



Entire, (of leaves) without dentation 

 or division. 



Ephemeral, short-lived, usually lasting 

 but a day. 



Epiblast, a lateral outgrowth from the 

 embryonic axis of some grasses. 



Epicarp, the outer layer of the pericarp 

 or fruit coat. 



Epicotyl, that portion of the seedling 

 axis above the cotyledonary node. 



Epidermis, the superficial layer of cells 

 covering a plant. 



Epigeal, (of cotyledons) expanding 

 above the soil surface. 



Epigynous, (of flowers) with all floral 

 parts conjoint and generally divergent 

 from the ovary at or near its summit. 



Etiolate, deprived of color or length- 

 ened owing to the exclusion of light. 



Exarch, applied to primary xylem in 

 which the progressive development of 

 the elements is centripetal. 



ExocARP, the outer layer of the pericarp 

 or fruit coat. 



Exogenous, arising from superficial 

 tissues. 



Fascicular cambium, the cambium 

 which gives rise to the secondary 

 vascular tissues of a bundle. 



Fiber, an elongated, thick-walled me- 

 chanical element. 



Filament, the part of the stamen sup- 

 porting the anther. 



Floral envelope, the perianth (calyx 

 and corolla). 



Flower, a shoot beset with sporophylls 

 (stamens and carpels). 



Follicle, a dry fruit consisting of a 

 single carpel which dehisces along 

 the ventral suture. 



