Fig. 101. Calamites (Calamitina) sp. From a specimen in the British Museum. (After Carruthers.) Slightly reduced.
The fragment of a Calamitina stem shown in fig. 101 is the counterpart of a specimen originally figured by Steinhauer[798] in 1818 as a species of Phytolithus. This may be specifically identical with C. Göpperti; but it is better to speak of so small a specimen as merely one of the Calamitina stems, to be compared with Calamites (Calamitina) Göpperti. The specimen measures 14·5 cm. in length and 7 cm. in breadth.
The form of pith-cast represented in fig. 100 is no doubt that of one of the Calamitina species, but as it is seldom possible to determine the connection between such casts and the particular species of stems to which they belong, they are often referred to as Calamites (Calamitina) approximatus (Brongn.). The specimen of which fig. 100 is a photograph was originally described and figured by Mr Kidston[799] from the lower Coal-Measures of Ayrshire. Both Calamites (Calamitina) Göpperti (Ett.) and C. (Calamitina) approximatus (Brongn.) are recorded from the Transition, Middle and Lower Coal-Measures[800].
B. Stylocalamites.
In the members of this sub-genus the branch-scars are either irregular in their occurrence or absent. In some Calamites the branch-scars are very few and far between, and other species appear to have been almost without branches; pith-casts of such stems may be referred to the sub-genus Stylocalamites[801].
An exceedingly common Calamitean cast, C. Suckowi Brongn. (fig. 82) affords a good illustration of this type of stem. In the specimen shown in fig. 82 we have a cast of a rhizome, which is rather exceptional in showing three branches in connection with one another. The appearance of the fossil suggests a rhizome, rather than an aerial shoot, bearing lateral branches; the narrowing of the branches and the rapid decrease in the length of the internodes towards the point of attachment being features associated with rhizomes rather than with aerial branches.
Calamites (Stylocalamites) Suckowi, Brongn. Fig. 82.
| 1818. | Phytolithus sulcatus, Steinhauer[802]. |
| 1825. | Calamites decoratus, Artis[803]. |
| 1828. | Calamites Suckowi, Brongniart[804]. |
| 1833. | Calamites cannaeformis, Lindley and Hutton[805]. |
For more complete lists of synonyms of this species reference should be made to Kidston[806], Zeiller[807], and other authors.