EOCENE EERNS. 



37 



This determination should be received at present with some hesitation, since we know 

 of no existing Eern possessing crowded secondary veins and free venules, and the venation 

 on the other hand resembles that of certain dicotyledons/ 



Phegopteris pr^-cuspidata. Bit. and Gard. Plate IV, figs. 8, 9. 



Ph. fronde pinnata, piniiis lanceolato-linearihus, elongatis, crenato-serratis ; nervatione 

 Goniopteridis 3Ieniscu, nervo primario pronmiente, recto ; nervis secundariis sub angulis 

 -60 — 75° orientihus, numerosis, tenuilus, simp)licihm,Jiexuosis; nervis tertiariis utrinque 

 4 — 6 e 7iervis secundariis angulis acutiorihus egredientibus, anastomosantibus, cafadromis ; 

 radiis interruptis vel obliteratis. 



Middle Bagshot, Bournemouth. 



The pinnae are linear-lanceolate, obtusely serrate, with the venation of Goniopteris, in 

 which all the ternary veins anastomose. It is referred to the Goniopteris Meniscii type, 

 ■because the rays are interrupted and not continuous. It is probably a Phegopteris, and, 

 indeed, differs only from P. cuspidata, Mett., in the following unimportant particulars : 

 the marginal teeth are rather more obtuse or crenate ; the midrib is prominent yet 

 less thick ; the secondary veins are sinuous instead of only curved upwards near the 

 margin, less close, and at more acute angles ; the lower ternary veins have a distinctly 

 catadromous origin ; the ramifications are usually very short, interrupted or abortive 

 instead of always present. Its similarity to Gymnogramma villosa of Brazil is also 

 striking. 



There are also certain resemblances between this and the Miocene forms Phegopteris 

 Helvetica {Lastrcea)y Heer,* Ph. polypodioides^ Wi^Ph. Stiriaca,^ also abundant at Bovey 

 Tracey. 



Heer would unite it with Ph. Bmburgi next described, considering it to be a fertile 

 rond of that species ; but although the venation in the only Bournemouth specimen is so 

 indistinct that I am not inclined to attach too much importance to it, yet it hardly seems 

 to justify the union. Pending the discovery of better specimens, I think they must be 

 considered distinct. 



The portion of a fertile frond figured is unique, and was obtained at Bournemouth, 

 together with a magnificent series of dicotyledonous leaves of large size and palms, from 

 one of the lower beds under the Coast- Guard Station, and therefore may be presumed from 

 its surroundings to have had a shady forest habitat, and to have required a high 

 temperature. 



1 Saporta has pointed out that the venation is not very dissimilar to that of the dicotyledonous genus 

 Andromeda, sub-genus Leucotfide. 



2 « pior. tert. der Schweitz.,' pi. vi, fig. 2, pi. cxliii, figs. 2 — 5. 



3 Ett., ' Monte Promina,' pi. ii, figs. 1 — 4 ; Heer, loc. cit., pi. c.xliv, figs. 1 — 3. 

 * Ung., 'Chlor. Prol.,' pi. xxxvi, Heer, loc. cit., pis. vii, viiii. 



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