Different genera have been founded on leaf-bearing branches of Calamarieae; apart from Archaeocalamites, already mentioned, and Autophyllites (Grand' Eury), in both of which the leaves were dichotomous, we have Annularia, Asterophyllites and Calamocladus (in Grand' Eury's limited sense), with simple leaves.
Compound Umbel of Dichotomous Cymes,Laurustinus.
In the Lower Carboniferous of Scotland Mr Kidston has found several specimens of a large dichotomous thallus, with a very distinct midrib; the specimens, referred to the provisional genus Thallites, much resemble the larger thalloid Liverworts.
Biparous Cyme (Dichotomous),including 3-5chotomou3 Cymes (Dichasium, Cymose Umbel, Anthela).
This genus, from the Permo-Carboniferous of Autun, is represented by large, fleshy, reniform leaves or leaflets, with radiating dichotomous venation; the vascular bundles have in all respects the structure of those in the leaves of Cycads or Cordaiteae.
In Dictyotaceae the apical cell occasionally divides longitudinally, and thus the dichotomous branching is provided for.
- Antlers small and simple, forming a single dichotomous fork; metatarsal gland absent; tail short; face moderately long; face-gland and gland-pit well developed; upper canines present in both sexes.
The leaves, which bear the sporangia, are dichotomous, and do not form definite cones, but alternate in irregular zones with the foliage leaves.
- Leaf-base of a Lepi- main stem terminated in dichotomous dodendron.
- The genus Lepidodendron, with very numerous species, ranging from the Devonian to the Permian, consisted of trees, with a tall upright shaft, bearing a dense crown of dichotomous branches, clothed with simple narrow leaves, ranged in some complex spiral phyllotaxis.