120 FOSSIL PLANTS. 



Lesquereux, Eeport Geol. Survey of Illinois, vol. ii. p. 441, 



Geol. of Pennsyl. vol. ii. pt. ii. p. 866. 



Eenault, Cours d. Botan. Foss. voL iii. p. 116, pi. xx. figs. 1-10. 

 Eost, De Fil. Ectypis, p. 26. 

 Schimper, Trait6 d. Pale"ont. Vege~t, vol. i. p. 506 (excl. syn. P. 



abbreviate/,). 



Zeiller, Princip. Ve"get. Foss. du Terr. Houil. p. 91, pi. clxix. figs. 1, 2, 3. 

 Flore Houil. des Asturies, p. 15. 



Hawlea polymorpha. 



Stur, Culm Flora, heft 2, p. 293. 



Scolecopteris polymorpha. 



Stur, Morph. u. Syst. d. Culm u. Carbonfarne, p. 107, fig. 21. 



Remarks. In the barren condition there are no satisfactory characters by 

 which this and the two following species can be distinguished ; 'their similarity 

 in this state is so great, that several authors have united them. In the 

 fructifying condition, however, Pecopteris polymorpha, Brongt. is essentially, 

 distinct from Pecopteris Miltoni, Artis, and Pecopteris abbreviata, Brongt. In 

 all three species the fruit is placed in stellate groups of from three to five 

 sporangia. In Pecopteris polymorpha the sporangia are produced upwards 

 and end in a setaceous point, in the two other species they rise little above 

 the surface of the pinnule. In Pecopteris abbreviata, according to Zeiller,* 

 the sporangia cover the whole lower surface of the pinnule. In Pecopteris 

 Miltoni, they form one row, placed about midway between the margin of the 

 pinnule and the central vein. Zeiller gives as the distinguishing character of 

 P. abbreviata, Brongt., from P. Miltoni, Artis, sp. ; that in the former the 

 fruit covers the whole of the under surface of the pinnule, whereas in the 

 latter it is marginal. In proof, he cites the original figure of Pecopteris 

 Miltoni, Artis, sp., where the fruit is shown to be placed on the margins of the 

 pinnules ; but this is an error of the draughtsman, for Artis, in speaking of 

 his plant says, " the fructifications seated on the back of the leaves are not so 

 closely seated on the margin as is expressed on the plate, neither is the rib so 

 round as represented. "t There is in the Collection a very fine specimen of 

 Pecopteris Miltoni, Artis, sp., in fruit, from the Forest of Wyre. The sporangia 

 are large, and although the groups form only a single row, they occupy 

 nearly the whole space between the midrib and the margin of the pinnule, so 

 really they cover the whole of the lower surface of the pinnule. This speci- 

 men occurs with well-preserved barren examples of Pecopteris Miltoni, I there- 

 fore feel quite convinced that the fruiting specimens belong to that species. 

 I think it probable, that eventually Pecopteris Miltoni and Pecopteris abbreviata 

 will be found to form only one species, and that Zeiller has been misled, by 

 the figure given by Artis, as to the fruit being marginal in P. Miltoni, but 

 at present I keep them separate until the differences indicated in their 

 fructification be more fully investigated. 



Horizon. Coal Measures. 



Localities. British. Northumberland : Newcastle-on-Tyne. Somersetshire : 



Camerton. 



Foreign. Bohemia : Podutha. France : Chazotte, St. Etienne. 

 United States : Illinois, Mazon Creek, Grundy Co. 



Pecopteris Miltoni, Artis, sp. 

 Pecopteris Miltoni. 



Boulay, Ter Houil. du Nord de la Francte, p. 31. 

 Brongniart, Prodrome, p. 58. 



Hist. d. Veget Foss. p. 333, pi. cxiv. 

 Fontaine and White, Perm, or Upper Carb. Flora, p. 65, pi. xxiii. figs. 2, 3. 



* Flore Houil. des Asturies, p. 12. 

 t Artw, I.e. p. 14. 



