20 INCERTZ SEDIS. 
A very similar fossil has been figured by Fontaine from the 
Potomac beds of Baltimore as ‘‘an undetermined plant”’;! his 
specimen is smaller, but very similar in form; it shows a circular 
orifice in the centre, a character not noticed in the English 
example. The Potomac fossil is described as more like a leaf- 
sheath of yuwisetum than anything else. Ettingshausen? has 
figured a small object from the Wealden of Zobing, described as 
a ‘* Patellenahnliches Gebilde,’”? which may be compared to our 
figured specimen. In the genus Phyllotheca there is a certain 
amount of resemblance to the present specimen in the form of 
the leaf-sheaths. Zigno’s figures of Phyllotheca equisetiformis, Zig.,? 
represent stems with nodes clasped by leaf-sheaths deeply divided 
into acute and slightly incurved segments. In the case of a 
detached leaf we should expect, however, to have a circular 
structure with a central aperture. In a leaf-sheath of Phyllo- 
theca Schtschuraroskii, Schmal.,4 from the Russian Jurassic rocks, 
there is also a certain similarity as regards size and general form. 
Specimen B. Pl. I. Figs. 8 and 9. V. 2328. 
Ecclesbourne. Rufford Coll. 
This specimen consists of a repeatedly branched structure bear- 
ing small and closely arranged leaves; the axes of the branches 
are distinguished in several places by the presence of a white 
mineralization substance in the form of fine longitudinal lines, 
suggestive of a slender and woody central cylinder; the general 
habit 1s somewhat stiff; length 3 em. 
Mr. Carruthers, to whom I showed the specimen, recognized a 
resemblance to the sporangiferous branches of some of the Lycopo- 
dium Phlegmaria group,’ and pointed out the possibility that the 
small carbonaceous patches shown in Fig. 9 in the axis of the left- 
hand leaves may be the remains of sporangia. In addition to these 
black patches the enlarged piece of a branch (Fig. 9) shows the 
pointed and slightly falcate leaves, which appear to occur in two 
1 Potomac Flora, p. 276, pl. clxxiii. figs. 11 and 11a. 
2 Abh. k.-k. geol. Reichs. vol. i. Abth. iii. No. 2, p. 32, pl. iii. fig. 20. 
3 Flor. foss. Oolit. vol. i. p. 60, pl. viii. fig. 5a, ete. 
4 Schmalhausen. Mém. Ac. Imp. St. Pétersbourg, sér. vii. vol. xxvii. No. 4, 
1879, pl. vi. fig. 3. 
5 Baker. Fern-allies, p. 19. 
