122 DUBLIN NATURAL HISTORY SOCIETT. 



ILLUSTRATIONS OF THE FOSSIL FLORA OF THE LOWER CARBONIFEROUS BEDS OF 

 IRELAND. Br THE REV. SAMUEL HAUGHTON, F. T. CD., AND PROFESSOR 

 OF GEOLOGY IN THE UNIVERSITY OF DUBLIN. 



Plate VXII. represents, on a scale one-half that of nature, a fine speci- 

 men of Knorria (named Sagenaria Veltheimii (Sternberg), and Knorria 

 imhricata (Giippert), by the German palaeontologists). It is a cast of the 

 woody axis of this genus, and exhibits well the dichotomous arrangement 

 of its branches, and the imbricated, spirally- arranged leaf- scars character- 

 ristic of the Lepidodendra, to which it is evidently allied. 



Locality : Hayntren, Saxony. 



Geol. horizon : Base of the Lower Carboniferous. 



I have introduced this for the purpose of contrasting it with the fol- 

 lowing : — 



Plate IX., Figs. 1 and 2. — Side view and cross section of imperfectly 

 preserved stem of plant, showing central coaly axis and longitudinal 

 striations on external surface ; natural size. I cannot refer this plant 

 satisfactorily to any known form. It is a cast of the woody axis of some 

 form of Lycopodiaceous or Endogenous plant ; but the central tube pre- 

 sents a structure different from that of any recent forms. 



Locality : Harry lock Bay, county of Wexford. 



Geol. horizon : Yellow sandstone, 380 feet below the lowest bed of 

 Carboniferous Limestone. 



Plate IX., Fig. 3. — Natural size ; stem of smaller branch of same 

 plant as last, showing bases of leaves at lower portion of external sur- 

 face. The peculiarity of this specimen consists in the spiral tube, filled 

 with coaly matter or peroxide of iron, which twines round the stem, as 

 shown in the figure. Professor Phillips, of Oxford, has suggested to me 

 that it may (possibly) be the stem of some kind of twining fern, which 

 has compressed the stem so closely as to penetrate below the external 

 surface. The bases of the spinous leaves are well shown in the figure. 



Locality : Harrylock Bay, county of Wexford. 



Geol. horizon : Same as last. 



