'^'"'™J NOTES ON CHARACTERISTIC SPECIES. 881 



right ano-le, ovate, round-ovate, or frequently more or less narro\vly 

 triangular, elongate and acute, generally briefly subpetiolate, cut alter- 

 nately to near the base or midrib into one to five close or distant, more 

 or less divergent, cuneate or rhom])oidal divisions, which in turn are 

 once or twice deeply or laciniately incised in narrow, simple, bifid or 

 trifid divergent lobes, each simple linear lobe or tooth having its mar- 

 gins parallel or but slightly converging upward to the very narrow, 

 obtusely rounded apex; lamina not very thick, finely longitudinally 

 lineate, apparently by rows of scaly epidermal cells parallel to the 

 nerves, which are often partially obscured. 



Nervation usually visible and of moderate strength; primary nerve 

 curving strongly outward from a very acute-angled, decurrent origin, 

 forking low, the divisions forking repeatedly to furnish a single nervil 

 for each lobule or tooth. 



Representatives of this interesting species are not rare in the lower 

 portions of the very thick sections of the Pottsville ser-es in the 

 Virginia, Tennessee, and the Alabama regions, as well as in the 

 Southern Anthracite field of Pennsylvania. While, however, the 

 specimens from some of the localities in the Southern Appalachian 

 coal fields are typical of the form delineated by Ettingshausen, the 

 form described above from the collection before me appears to differ 

 slightly from the Old World types ^ by the generally slightly more 

 flexuose pinnse, a little g-reater coherence of the lobes, and a rather 

 less marked tendency of the latter to curve outward. In the second 

 particular they are extremely close to the fragments illustrated by Stur.^ 

 As may be noted in the fragments illustrated in PI. CLXXXVIII, 

 Fig. 1, considerable difference exists in the form and elongation of the 

 pinnules in different portions of the frond. 



The essential characters of the species are the lax habit, the distant, 

 large, very open, and short pedicellate pinnules, the elongated and 

 loose development, with deep, open sinuses, of the subdivisions, and 

 the linear, very blunt or round-pointed lobules which are hardly con- 

 tracted ])elow the middle. The somewhat irregular lineation seen in 

 the lamina of the Pennsylvania specimens is clearly visible with a 

 weak lens. Frequently the apices are partly l)uried in the matrix, or 

 the margin is a little re volute, so as to give the lobules a sharp profile 

 on the rock, ])ut when carefully worked out the tip is found to be 

 rounded. The large pinnules seen in PI. CLXXXVIII, Fig. 1, are 

 comparable to figs. 7 and S, pi. ix of the first part of the Culm-Flora. 



Spliniopterk furatta Brongn., a species whose pinnules resemble 

 those of 8. patentissima^ is distinguished from the latter by the more 

 rigid pinnae, the closer and more compact pinnae and pinnules, which 



' Ettingshausen, Foss. Fl., Mahriseh-Sfhlesischcn Dachschiefers, p. 26, pi. vii, flg. 4, text-fig. 13, 

 2Culm-Flora, I ; Die Culm-Flora d. .Miihri.stfh-Sehlesi.sehen Dachschiefers, p. 36, pi. ix, figs. 1-9. 

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