"Vol. 69.] THE CLEVELAND DISTRICT OF YORKSHIRE. 243 



of anastomosis. The pinna? are comparatively crowded on the 

 rachis, the centres of their bases being about 5 to 10 mm. apart. 

 There is a specimen in the York Museum, probably of a species 

 identical with the one just described. Prof. Seward has kindly 

 supplied me with a photograph of it (reproduced in PI. XXVI). 

 It is a well-preserved smaller frond, with a rachis 2 to 3 mm. 

 in breadth, bearing linear pinnae 5 to 7 mm. broad and of con- 

 siderable length. The bases of the pinna? are decurrent, and 

 numerous fine parallel veins are present which do not anastomose 

 but occasionally fork, The specimen is labelled as coming from 

 the Lower Shale, Scarborough, and had been identified as Ctenis 

 falcata, indicating its close resemblance to the shape of that species. 

 From the foregoing description it will be seen that these fronds 

 are closely allied to those from Sutherland, but differ from them 

 in possessing narrower pinnae more obliquely placed, and bearing 

 rather less resemblance to Ctenis in their form. They consequently 

 approach very nearly to Zamites, and the species now under con- 

 sideration was originally described by the Rev. G. J. Lane * as 

 Zamites bucliianus ; they are to be distinguished from this, however, 

 by the lateral disposition and by the decurrent bases of the pinna?, 

 although in the absence of a large series of specimens we cannot 

 be absolutely certain about the latter character. 



While establishing a new species for the reception of these forms, 

 I must note that the material at present available makes it difficult 

 for anyone to be certain as to their exact relationships to other 

 frond-forms. 



Ginkgoales. 

 Ginkgo digitata (Brongn.). 



['Hist. Veget. Foss.' 1828, p. 219 & pi. Ixi bis, figs. 2-3.] 

 One very good specimen 2 shows a leaf which is about 7 cm. 

 broad. The stalk is not seen ; the lamina is divided nearly to the 

 base into three or four segments, each of which is again divided 

 half-way down. The venation is clearly seen, and shows the usual 

 repeatedly forking character, so that in this respect, as well as in 

 form, this specimen closely resembles the common Yorkshire type. 



Baiera longifolia (Pomel). (PI. XXV, figs. 3 & 4.) 



[Versamml. Gesellsch. Deutsch. Naturf. in Aachen, 1847, p. 339.] 

 One of the commonest fossil-plants at Marske is a Baiera with 

 large leaves divided into long linear segments. I have not yet 

 obtained an absolutely complete specimen, but one of the examples 

 figured (PI. XXV, fig. 3) had a length of 12 cm. measured from 

 the region of the first dichotomy outwards, and the complete leaf 

 must have probably exceeded 18 cm. in length. The basal portion 



i Lane (10) p. 264 & fig. 



2 Figured in Proc. Cleveland Nat. Field-Club, vol. ii (1910) pt. 4, p. 206. 



