In other species, however, a peculiar type of polystely is met with, in which the original diarch stele gives rise to se-called dorsal and ventral stelar cords which at first lie on the surface of the primary stele, but eventually at a higher level separate from it and form distinct secondary steles resembling the primary one.
The gaps, are, however, often filled as they are formed by the development of external conjunctive tissue immediately above the points at which the bundles begin to bend out of the stele, so that sharply defined open gaps such as occur in fern-steles are but rarely met with in flowering plants.
The radial structure is characteristic of all root-steles, which have in essential points a remarkably uniform structure throughout the vascular plants, a fact no doubt largely dependent on the very uniform conditions under which they live.
The inhabitants frequently rebelled and were as often subdued; records of these repeated conquests were set up by the Egyptian kings in the shape of steles and temples; of the latter the temple of Amenhotep (Amenophis) III.
Besides a number whose names have been discovered in cartouches at Jebel Barkal, the following, of whom all but the third have left important steles, can be roughly dated: Tandamane, son of Tirhaka (667-650), Asperta (630-600), Pankharer (600-560), Harsiotf (560-525), Nastasen (525-500).
Many hundred funeral steles were removed by Mariette's workmen, without any record of the burials (Mariette, Abydos, ii.
The stem contains one, two or several steles; in one species the stele is tubular.
The anatomy of the stele in the stem exhibits on the whole a progression from a solid protostele through a tubular solenostele to one or more circles of separate steles derived by the breaking up of the solenostele.
The stem, from the ground tissue of which sclerenchyma is absent, has a complicated system of steles arranged in concentric circles; the thick roots, the central cylinders of which have several alternating groups of xylem and phloem, arise in relation to these.
The anatomy of the stem differs in the four recent genera of this order, and presents a series possibly illustrating the origin of a number of concentric steles from a solid stele, the intermediate step being represented by those forms in which the central cylinder is tubular.
The stem in the more primitive forms has a tubular stele (solenostele); for the most part two to many steles, arranged in a ring (dictyostele).
The structure is often a complex one, the central region containing an elaborate system of numerous anastomosing steles, accompanied by sclerenchyma; the cortex is permeated or coated by a multitude of adventitious roots, forming a thick envelope to the stem.
Anglica, the simplest species known, the steles are uniform, and usually only three in number; the structure of the stem is essentially that of a polystelic Heterangium.
Leuckarti, the arrangement is more complicated, the steles showing a differentiation into a central and a peripheral system; the secondary growth was extensive and unequal, usually attaining its maximum on the outer side of the peripheral steles.