362 DR R. KIDSTON 



each end of the xylem to supply the pinnae traces, which, as in Zygopteris duplex, 

 possibly divided into two in their course through the cortex. 



The metaxylem is multiseriate as seen in transverse sections of the trachea?, while the 

 protoxylem is apparently scalariform. 



The soft elements of the stele have all decayed, and are only represented by carbon- 

 aceous fragments around its periphery. 



The remains of the endodermis are seen at fig. 1 , end. , and outside of this lies the 

 inner cortex, composed of four or five rows of delicate parenchyma. This is succeeded 

 by the outer cortex, formed of thick- walled prosenchyma, the component elements of 

 which vary somewhat in the size of their lumen, but there is no regular arrangement of 

 the larger and smaller elements. The peripheral portion of the cortex consists of smaller 

 elements, but it is much destroyed and seems to have been of a more delicate structure 

 than the zone lying immediately within it. 



If one compares the description of Dineuron ellipticum with Renault's description 

 of his Dineuron pteroides, the wisdom of placing the Pettycur plant in the genus 

 Dineuron may at first sight be questioned ; but if the figure of Dineuron pteroides be 

 carefully examined, it will be seen that the tissue which occupies the central portion of 

 the stele has much more the appearance of xylem than of parenchyma, as supposed by 

 Renault. This circumstance, supported by the structure of the Pettycur plant, which 

 agrees so completely with Dineuron in other respects, has led me to adopt this view, 

 and a similar opinion seems to have been accepted by Mons. Paul Bertrand in his 

 proposed classification of the Zygopteridese* 



II. Botryopteris antiqua, Kidston, n. sp. (Plate, figs. 4-12.) 



Three stems of Botryopteris antiqua are shown on Plate I. figs. 4, 6, 7. The one 

 given at fig. 4 shows two attached petioles, and that at fig. 7 a single attached petiole, 

 while the stem at fig. 6 illustrates the branching of the stele (s.', s") and also shows a 

 petiole just freed from the stem. 



Characteristic of the family to which it belongs, Botryopteris antiqua has a very 

 small stem stele, when considered in relation to the size of the petioles to which it gives 

 rise. The stele of the specimen seen at fig. 4 is only # 40 mm. in diameter, while those 

 of figs. 6 and 7 have a diameter of 0'50 mm. 



The stem is irregular in form, owing to the departure of the petioles and roots. The 

 cortex is formed of thick-walled prosenchymatous cells of small diameter and without 

 intercellular spaces, the larger elements being placed towards the outer surface of the 

 stem, which bears numerous hairs formed of a single row of cells. 



The circular stem stele is formed of very small tracheae, without any admixture of 

 parenchyma. Stem protoxylems are not distinguishable (fig. 5). In longitudinal 



* " Classification des Zygopteridees d'apres les caraeteres de leurs traces foliaires," Comptes rendus, 4th November 

 1907. 



