98 



E. A. Neicell Arher — Plants from Kent Coal-field. 



The nodal region is unfortunately very imperfect, tliough there can 

 be little or no doubt that the upper part of Fig. 1 really represents 

 a node, or that the ridges of successive internodes alternate. No 

 reliable evidence exists either of infranodal canals or of leaf-scars. 

 As to the interpretation of the specimens, it is of course diflS.cult 

 to draw any definite conclusions from the present material. The 

 anastomosing of the ridges of the internodes is, however, a perfectly 

 definite feature, though one would wish for more perfect examples of 

 the nodes in order to determine whether these specimens represent 

 the external impressions of a stem, or the pith-casts of a plant allied 

 to Calamites. I am inclined to adopt pr<jvisionally the former view. 

 The evidence of roots and of root-scars favours the suggestion that we 

 are dealing here with the external surface of a stem. The absence of 

 infranodal canals, though not conclusive in the present material, also 

 supports this conclusion, so far as it goes. 



The external surfaces of Calamite stems are very varied. Some are 

 almost smooth, while others possess ridges and grooves on the inter- 

 nodes, not very dissimilar to those of the pith-casts. The inter- 

 pretation of these specimens as external impressions, characterized 

 by a reticulation of ridges on the internodes, naturally presents less 

 difficulties than the supposition that we are dealing here with pith- 

 casts. On the latter hypothesis, we should he led to imagine that the 

 vascular bundles of this plant must have anastomosed frequently, as 

 exhibited by the lozenge-shaped areas between the ridges. This is 

 quite contrary, of course, to any evidence we have from petrified 

 specimens. I think a new generic name, Dictyocalamites, may be 

 proposed for such fossils, whether they eventually prove to be external 

 surfaces or pith-casts. 



The following is a diagnosis of the new genus : Segmented casts 

 or impressions of Equisetalean affinity, similar in habit to those of 

 Calamites, the internodes of which are characterized by a reticulation 

 of ridges. 



I have pleasure in naming the species after Dr. Malcolm Burr, 

 r.G.S.,^who has very kindly presented the specimens figured here to 

 the Sedgwick Museum, Cambridge. 



Pterophtlltjm sp. (PI. V, Figs. 2 and 4.) 



The other new plant, which is of nearly equal interest, is repre- 

 sented by some fragments of leaves, which appear to belong to the 

 genus Pterophyllum. They were obtained from the same boring at 

 Barfreston, at a depth of 1,834 feet, in the Transition Coal-measures. 



The two specimens figured on PL V, Figs. 2 and 4, show a some- 

 what stout rachis with fragments of pinnules still attached. None 

 of the latter, however, are complete. The longest leaflet, slightly 

 exceeding 1 cm. in length, is seen at the top of Fig. 2, which is 

 enlarged nearly twice. The leaflets are fairly distant from one another, 

 from 1 to 1"5 mm. broad, and appear to be slightly contracted at the 

 base. Each has three or more parallel nerves, which fork occasionally 

 near the base. These are seen on Fig. 4, which is three times enlarged. 



There appears to be little doubt that these leaves are of Cycado- 

 phytean affinity. I have shown them to Professor Nathorst and 



