526 Scientific Proceedings, Royal Dublin Society. 



25. Zeiller, R. : Elements de Paleobotanique, 1900. 



26. Weiss, F. E. : A Stigmaria with Centripetal Wood. Annals of Botany, 



vol. xxii. 



27. McLean, R. C. : Two Fossil Prothalli from the Lower Carboniferous 



Measures. New Phytologist, vol. si, 1912. (Plates v and vi.) 



28. Seward, A. C. : Fossil Plants, vol. ii, p. 257. University Press, Cam- 



bridge, 1910. 



EXPLANATION OF PLATES. 

 (The illustrations are from photographs taken mostly by Mr. T. Price.) 



PLATE XXXV. 



Fig- 



1. Portion of a stem, slightly enlarged, of Bothrodendron kiltorkense, showing 



attached foliage. The specimen illustrated is part of the Lepidodendron 

 Griffithii of Brongniart's letter to Dr. Griffith. (The Botanical Division, 

 National Museum, Dublin.) 



2. Portion of the stem, showing more or less closely crowded leaf-scars in upper 



part in whorls and more distant spirally arranged leaf-scars in lower part 

 (f). Compare the lower part with the stem surface in fig. 1. (Geological 

 Museum, Trinity College, Dublin). 



8. Surface of stem showing zonation. The leaf-scars on the left are less 

 zonately arranged. The stem-surface is like that in the upper half of 

 fig. 2, slightly enlarged (|). It appears to illustrate Heer's interpretation 

 of Haughton's C. minutum. (Geological Museum, Trinity College, 

 Dublin.) 



4 and 5. Calamitoid impressions of stems in -STworrm-stage. The upper end of 

 fig. 5 on the right gives some indication of the spirally arranged leaf-scars 

 (i). (Geol. Surv. Ireland Collections). 



PLATE XXXVI. 



Fig. 



1. This impression of Bothrodendron kiltorkense shows that the stem divided 



dichotomously, and bore apical tufts of long subulate deciduous foliage 

 leaves. The right-hand prong shows the stem-surface with almost 

 horizontal whorls of leaf-scars (i). (See fig. 1, PI. XXXVII.) (Geol. 

 Surv. Ireland Collections.) 



2. An older forked stem, prongs unequal in thickness. In addition to the leaf- 



scars the longitudinal striation is observable (f). (Geol. Surv. Ireland 

 Collections.) (This figure is numbered " 3 " in error.) 



