GYMNOSPERMtE. 



49 



The Bournemouth specimens are linear-lanceolate, the margins being parallel for 

 nearly the entire length ; the apex is acute and the base broadened and sessile. No 

 venation is discernible except the midrib, which shows more strongly on the back of the 

 leaf than on the face. Their condition of preservation betrays a very coriaceous con- 

 sistence. Figs. 9 and 10, both representing imperfect leaves, exhibit a total length of 

 over three inches, with a breadth of only three-sixteenths of an inch, but these may possibly 

 be neither the same species as the other leaves, nor even Coniferous. A fine and perfect 

 typical example of true Podocarpus is delineated in fig. 7. The length of the leaf is 

 seven millimetres, the breadth barely three millimetres ; the apex is sharply pointed and 

 mucronate, the base sessile, about one millimetre broad ; the midrib strong and distinct, 

 and the colour a deep brown. The leaves from Mull are identical with it in every respect, 

 save colour, and apparently also a half leaf from Antrim. This is the more remarkable 

 since at Bournemouth the species is strictly confined to the Uppermost " Coastguard 

 Bed," and has never been met with in any of the other numerous beds, from which large 

 collections have been made. The remaining specimens from Bournemouth agree well 

 with it, except fig. 8, which is a much smaller leaf, becoming broader towards the apex, 

 with a slender, petiolated base, and thin and sharply defined midrib. Our species differs 

 materially in its broadly sessile and articulated base, and narrow linear form with parallel 

 margins, from all the many similar Podocarp leaves described from the Continental 

 Eocenes. It bears the greatest resemblance to P. gracilis. Sap., from Aix, and 

 P. Peyriacensis, Sap., from Peyriac, yet differs from these in the sessile base and 

 mucronated apex. 



The single leaf known from Alum Bay (fig. 1 5) has a different character, tapering to 

 an apparently petiolated base and a pointed, but not mucronated, apex. This measures 

 seven centimetres in length and six millimetres in breadth ; and while agreeing closely 

 with F. plana, Wat., P. pfoxima, Sap., and F. eocaniica, Ung., differs very markedly 

 from the Bournemouth type. No venation is discernible, except the strongly marked 

 midrib, and the leaf was obviously coriaceous. Figs. 13 and 14 represent much smaller, 

 and also very coriaceous, leaves from Hordwell, which, if referable to Podocarpus, would 

 probably belong to another species. 



Unger,^ who first described them, explains the microscopic leaf-structure of Podo- 

 carpus in great detail, as well as that of the wood, which he also met with fossil. ]\Iore 

 than a dozen extinct species have been made from the Tertiary leaves of this type, and 

 though Heer has united several, such as P. miicronulata, Ett., P. hmringiana, Ett., and 

 P. taxites, Ung., about eight species njmain. Some of these can perhaps scarcely be 

 regarded as satisfactory ; and it docs not appear, in the present state of our knowledge, 

 that any useful purpose can be served by adding further to thera. The broad fact is of 



1 ' Sylloge plantarum fossilium,' pi. 31, pp. 10 — 12. The specimens were from the Wetterau. He 

 considered the arrangement of stomata, which he represents magnified 100 and 360 diameters, to be most 

 like that existing in P. nuhigcena of Chili. 



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