Professor A. C. Seicard — Fossil Plants from Cape Colony-. 483 



by oval or circular depressions, or, ia the casts, by rather broad 

 truncated ridges. These two forms, shown in Figs. 1-4, I regard as 

 specifically identical, a conclusion which receives support from, an 

 examination of the much richer material described by Nathorst from 

 the Devonian of Bear Island.^ 



Fig. 4. This is a good example of the smaller form of branch in 

 which the axis, 1*2 cm. wide, is dichotomously branched, and the 

 surface bears numerous small oval or circular scars. This specimen is 

 probably identical with one previously figured' from the Port Alfred 

 range, and now in the British Museum collection, and with some of the 

 specimens figured by Schwarz. A similar form has been figured by 

 Nathorst as Bothrodendron Carneggianum (Heer) ^ from Bear Island, 

 and some of the examples of B. hrevifolnim and B. kiltorkense,^ 

 described by the same author, bear a striking resemblance to the 

 African fossils. 



The material hardly justifies a decided opinion as to the specific 

 identity of the northern and southern plants, but it is at least clear 

 that they represent closely allied types. ; ' 



The specimen represented in Fig. 3 shows more clearly the small 

 scars which are disposed spirally and in horizontal rows. The 

 horizontal arrangement is a conspicuous feature of several of the Bear 

 Island examples of Bothrodendron. Several acicular leaves are seen 

 on the left-hand side of this specimen The larger form is illustrated 

 by the specimens shown in Figs. 1 and 2. 



In the example shown in Fig. 2 the upper surface bears slightly 

 raised ridges terminating in scars. On the lower surface, that is the 

 impression of the cast, the scars are clearly seen as depressions. The 

 smaller specimen shown in Fig. 1 suggests at first sight a comparison 

 with SigiUaria owing to the prominence of the rounded ribs. There 

 is a close resemblance between this specimen and some of thosiS 

 figured by Nathorst as Bothrodendron Jciltorkense in the Knorria 

 condition from Bear Island. Some of the casts are those of branches 

 in a partially decorticated condition ; the scars are not the actual 

 leaf-scars as they appeared on the surface of the living plant, but 

 casts of gaps in the more external cortex. These gaps were formed 

 by the decay of a sheath of delicate tissue which surrounded each 

 leaf-trace as it passed through the cortex of the branch on its way to 

 a leaf. The uneven surface of the scars as seen in Fig. 1 is the result 

 of fracture of the slender argillaceous casts of the leaf-trace gaps. 



jS^one of the specimens examined retain the original surface 

 characters ; all are more or less decorticated. It is therefore im- 

 possible to say whether the surface of the branches exhibited the fine 

 sculpturing characteristic of Bothrodendron or the delicate reticulum 

 which distinguishes Weiss's genus Pinakodendron.^ None of the 



1 Nathorst, Konql. SvemJca Vetenskaps-Akad. Hand., 1894, Bd. xxvi, No. 4 ; 

 ibid., 1902, Bd. xxxvi, No. 3. 



2 Seward, loc. cit., p. 89, fig. 8. 



^ Kongl. Vetenskaps-Akad. Sand., Bd. xxvi, pi. xiv, fig, 10. 

 * Ibid., Bd. xxxvi, pis. xi, xii. 



5 Kidstoa, Trans. R. Soc. Edinburgh, 1903, vol. xl, pt. iv, p. 797, pi. i, 

 figs. 9-11. 



