The Post- Tertiary Deposits of Elie and Largo Bay. 105 



existence of a meristem layer between the outer and inner 

 portions of the bark, as also with the comparison I have in- 

 stituted between the central mass of the stem and a central 

 vascular bundle, with its investing sheath. As to any relation 

 between the increase of the bark from a meristem and the 

 acquisition of arborescent dimensions by Lepidodendroid 

 stems, Professor Dickson reserves his opinion. 



Explanation of Plates. 



( The same letter indicates the same part in the various figures. ) 

 a. Central vascular bundle, a'. Small scalariform vessels of foliar system ; 



a". Large scalariform vessels of vascular bundle, a'". Parenchymatous axis 



of reticulated and non-reticulated (?) cells. 



h. Foliar vascular bundles, embedded in traces of the bundle sheath. 



c. Space originally occupied by the bundle sheath. 



d. Inner portion of bark, 



e. Channel through which foliar vascular bundle passed to leaf. 

 /. Meristem or formative zone. 



g. Outer portion of bark. 



h. Leaf base. 



i. Foliar vascular bundles. 



Plate II. 

 Leindodendron selaginoides. 

 Fig. 1. Longitudinal section of portion of stem— V. 

 Fig. 2. Transverse section of portion of stem — V^. 



Fig. 3. Transverse section of portion of inner and outer parts of bark, 

 showing meristem layer situated between them — y>. 



Fig. 4. Longitudinal section of portion of central vascular bundle, showing 

 foliar vessels, large scalariform tubes, and reticulated and non-reticulated 

 parenchyma of axis — ^f^' 



Lepidodendron Harcourtii. 

 Fig. 5. Transverse section, showing junction of inner portion of bark and 

 bundle sheath — Y*. 



Plate II. a. 



Lepidodendron selaginoides. 

 Fig. 1. Central vascular bundle — '^^. 

 Fig. 2. Transverse section of stem — f- 



VII. Notes on the Post- Tertiary Deposits of Elie and Largo 

 Bay, Fife. By E. Etheridge, Jun., Esq., President. 



(Read 16th January 188L) 



The post-tertiary deposits in the neighbourhood of Elie and 

 Errol have formed the subject of a valuable paper by the 



