116 WEICHSELIA. 



18S3. lonchopteris ManteUi, Renault, Cours tot. foss. vol. iii. p. 167. 



1888. Weichselia Ludmica, Schulze, Flor. subhercyn. Kreid. p. 14. 



1889. Lonchopteris ManteUi, Bristow, Geol. I. Wight, p. 258. 



1890. Weichselia erratica, Nathorst, Arch. Ver. Freund. Nat. Mecklenb. 



Jahr. xliT. p. 1, pi. i. figs. 1 and 2. 

 1890. Pecopteris Geyleriana (in part), Nathorst, Denksohr. k. Ak. "Wiss. 

 math.-nat. CI. vol. Ivii. p. 49, pi. iv. fig. 3 (not the other figures 

 of this species) . 



Type. Eragments of pinnae ; pinnules sto-wing venation. The 

 specimens on ■whicli the genus Weichselia was founded are much, 

 larger, and consist of long pinnae attached to a broad rachis ; no 

 venation shown. 



The first diagnosis of Weichselia Ludovicee is that given by 

 Stiehler in 1857; the earlier definitions of the English species, 

 Lonchopteris ManteUi, were founded on much smaller specimens 

 than those which Stiehler had before him : — 



" Erons bipinnata, expansa, maxima (5-6-8 pedalis) ; rhachis 

 valida, profunde sulcata, apieem versus tenuissime excurrens ; 

 pinnae terminales subverticales, elongatae, anguste lineares, remotse 

 (distantes), reliquae horizontales, convexae, approximatse, lineari- 

 lanceolatse, ad 18 poU. usque longae, tV poU- latae, omnes basi 

 discretae; pinnules perbreves, oblongae, obtusae, integerrimse, approxi- 

 matse, fructiferae medio, canaliculatae, ambitu contractae, steriles 

 subplanae.'" 



The following definition includes most of the important characters 

 in this peculiar type of fern : — 



Erond bipinnate, rachis broad and rigid, pinnae alternate, very 

 long, of uniform breadth and with prominent axes ; pinnules entire 

 with obtusely rounded apex, a midrib and reticulate secondary 

 veins, oblong, except towards the distal ends of pinnae, where they 

 become more or less triangular in shape and have pointed apices, 

 attached by the entire base, separate and not confluent ; the stiff 

 and thick pinnules are usually inclined towards the axis of the 

 pinna, and the two rows form with the axis an open V instead of 

 lying in a horizontal position. 



The earliest figures and description of Weichselia ManteUi 

 (Brong.) are usually attributed to Mantell in the year 1824; the 

 paper to which reference is made was written by Stokes and Webb, 



' Palseontographica, vol. v. 1867, p. 75. 



