Seed Cone: generally woody; bracts, scales generally persistent; scale not peltate, fused to or free from subtending bract.
Acrophorus is characterized by having a cordate and often persistent scale at the bases of costae, membranaceous and semi-globose indusia, a few multi-celled septate clavate paraphyses on the lower portion of the sporangiate stalk, and a few short multi-celled clavate appendages on the margins of scales at the stipe bases [ 33- 35].
Flower: generally bisexual, radial; sepals and petals similar, persistent, scale-like, green to brown or +- purple-black; stamens generally 3 or 6, anthers linear, persistent; pistil 1, ovary superior, chambers generally 1 or 3, placentas 1 and basal or 3 and axile or parietal, stigmas generally > style.
Fruit: +- obconic, ray fruit 3-angled, disk fruit 2- or 4-angled; pappus 0 or 2--7 persistent scales.
Seed: wing persistent on scale.
However, Larsson et al. (2010) showed temporally stable patterns of differentiation among Skagerrak, northern Baltic and Bothnian bay herring populations over a 24 year period using the same set of nine microsatellite loci, suggesting a persistent large scale population structure.
A persistent large-scale clock-wise circulation around an upper-level low-pressure zone located close to the Pole is clearly visible at any time.
We report the detection of persistent, global-scale bands of magnetized activity on the Sun that slowly meander westward in longitude and display Rossby-wave-like behaviour.
As a result of these severe temperature differences, there is a persistent, large-scale, low-pressure zone that rotates in a cyclone-like fashion at each pole: from west to east.
We believe this is the main reason behind the inability of the UCSD team to win the challenge, which finished in the sixth position despite persistent large-scale attacks.
Starting from an arbitrarily small field, the flow of a conductive fluid, driven by some energy source, can result in a persistent large-scale magnetic field that can also show a variety of dynamical changes including polarity reversals.
