256 MANUAL OF MODERN VITICULTURE. 



NITROGEN A colourless gas composing four-fifths of the atmosphere by 

 volume. It is incapable of supporting life, but forms many important 

 compounds, as ammonia, nitric acid, &c., and is a constituent of all 

 organized living tissues, animal or vegetable. 



NODE (Bot.) The joint of a stem, or the part where the leaf is inserted. 

 NODOSITIES Small swellings produced on vine roots by phylloxera. 

 NODI:LE A round mass of irregular shape. 

 NORMAL According to an established rule. (Geom. ) Perpendicular to 



a surface or forming a right angle with it. 



NUCLEUS (Bot.) A wh'ole seed, as contained within the seed coats. 

 NUTRITION A process or series of processes by which the living organism 



is maintained in its normal conditions of life and growth 

 NUTRITIVR MATTERS Matters having the quality of nourishing. 

 OBTUSE Not pointed or acute ; blunt. 



OCHEROUS SOILS Containing an impure earthy ore of iron, or a ferru- 

 ginous clay. Such soils are usually red or yellow. 

 OOLITIC A great series of sec mdary rocks, so called from the texture of 



some of its members, which appear to be made up of small egg-like 



calcareous bodies. 

 OOSPORE (Bot. ) A special kind of spore resulting from the fertilization of 



of an oosphere by antherozoids. 



OPERCULUM Any lid-shaped structure in a leaf or flower. 

 ORBICULAR Having a spherical form. 

 OVA, sing. OVUM (Bot.) Eggs. 

 OVATE (Bot.) Having the snape of an egg, that is to say, an oval border 



at the base. 



OVOID (Bot.) Resembling an egg in shape. 

 OVULE, of plants The seed in the earliest condition. 



OXFORDIAN (Geol.) Applied to rocks of a certain age in the Jurassic series. 

 PARABOLA. A kind of geometrical curve ; one of the conic sections formed 



by the intersection of the surface of a cone with a plane parallel to one 



of its sides. 



PARASITE (Bot.) A plant living upon or in another plant. 

 PARENCHYMA (Bot.) The soft cellular substance of the tissues of plants, 



like the pulp of leaves. 

 PEDICLE or PEDICEL (Bot ) A stalk which supports one flower or fruit. 



One of the many divisions of a peduncle. 

 PEDUNCLE (Bot.) The stem or stalk which supports a cluster of flowers 



or fruits. 



PENTAGONAL LEAF Having five sides. 



PERMEABILITY The quality or state of being passed through. 

 PETALS (Bot.) The leaves of the corolla, a second circle of organs in a 



flower. 

 PETIOLAR SINUS Depression between two adjoining lobes into which the 



petiole is inserted. 

 PETIOLE A leaf stalk ; the stalk connecting the stem with the blade or 



limb. 

 PHYSIOLOGICAL Relating to the science of the functions of living 



organisms. 



PHYSIOLOGY Study dealing with vegetable or animal life, 

 PINCHING (Hort.) Operation consisting in cutting about one inch off the 



extremity of young shoots a little before or directly after florescence. 

 PISTIL (Bot. ) The female organs of a flower, which occupy a position in 



the centre of other floral organs. The pistil is generally divisible into 



the ovary, the style, and the stigma. 

 PITH (Bot.) The soft, spongy substance in the centre of the stem of many 



plants. 

 PLANE or PLAIN A flat, level, smooth, even surface. 



