158 T^XIOPTEHIS. 



1890. Oleandridiuin vitiation, Schimper, in Zittel's Handbuch, p. 133, 



fig. 107. 



1892. Taniopterls vittata, Fox-Strangways, Tab. Foss. p. 136. 

 1894. Cf. Tteniopteris vittata, Raciborski, Flor. Krak. pi. xx. figs. 9 and 10. 

 1897. ? Oleandridiuin vitiation, Bartholin, Danmarks Geol. Anders, fig. 8. 



Type-specimen. ? Natural History Museum, Paris. 



Frond simple, linear-lanceolate, reaching a length of more than 

 20 cm. and a breadth of 3 cm. The lamina increases gradually in 

 breadth from the petiole and tapers gradually towards the apex. 

 Numerous secondary veins are given off at right angles from 

 a broad midrib ; these are simple or forked ; the branching of the 

 lateral veins may take place close to the midrib, in the marginal 

 or in the intermediate portion of the lamina. 



There is a close agreement between the English specimens of 

 Tceniopteris vittata and the species T. tenuinervis, Brauns, as 

 figured by Schenk * and other authors, but in dealing with leaves 

 of the Tcsmopteris type it is practically hopeless to attempt to 

 distinguish between closely allied and identical forms. 



Unless its sori or sporangia are preserved, it is impossible to 

 determine the family of ferns to which Tceniopteris leaves should 

 be referred ; this simple type of leaf is met with in several recent 

 genera, and is of little or no value as an indication of affinity. 

 Taniopteris vittata is one of the commonest fossils from the 

 Yorkshire coast rocks. 



39,217. PL XVI. Fig. 1. 



The lower part only of the specimen is shown in the figure. 

 The lamina is 20 cm. long, and the slightly curved petiole 2*5 cm. ; 

 the latter appears to terminate in a fairly clean-cut face, which 

 is probably the actual base by which the leaf was attached to 

 a rhizome. This feature suggests a comparison with the leaves 

 of the recent fern Oleandra neriiformis, Cav., which become cut 

 off near the base of the petiole by a well-marked absciss-layer. 

 The lamina in its broadest part measures 3 cm. ; the lateral veins 

 are seen to fork at varying distances from their point of origin 

 from the broad midrib. 



1 Schenk (67), p. 101, pi. xxv. Vide also Bartholin (92), pi. ix. fig. 7. 



