RAVENHEAD COLLECTION IN THE BROWN FREE LIBRARY AND MUSEUM. 405 



Zeiller, in his admirable work on the Flore foss. d. bassin houill. d. Valenciennes, 

 gives, on his pi. i. figs. 1-4, drawings of a fern he identifies as Sphenopteris trifoliolata, 

 Artis, sp. None of these figures are, however, according to my view, referable to the 

 true Sph. trifoliolata, but to Sph. obtusiloba. Though the pinnules of some of Zeiller' s 

 figures show a trilobate segmentation, they are much more solid, and altogether want 

 the light and diffuse appearance of the pinnules of Sph. trifoliolata. I also fear that 

 the union of Sph. numularia with Sph. trifoliolata, as proposed by Zeiller, is inad- 

 missible. I am led to this conclusion from the examination of specimens of Sph. 

 trifoliolata from the same horizon as that from which the type was procured, and 

 therefore do not think that I can be mistaken in the characters of the true plant. 



Sphenopteris Marratii approaches very closely to Sphenopteris (Diplothmema) 

 avoldensis, Stur, # but seems to differ from it in the pinnae and pinnules being more 

 obtuse, and according to the description of Sphen. avoldensis, Stur, sp., it must have 

 been of more delicate texture. Dr Stur here again gives no enlarged drawings of the 

 segmentation of his species, without which a satisfactory comparison of these small 

 pinnuled Sphenopterids is almost impossible. 



I have pleasure in naming the Eavenhead species after Mr Marrat, who was the first 

 to publish a list of the Ravenhead ferns. 



Sphenopteris obtusiloba, Brongt. 



Sphenopteris obtusiloba, Brongt., Hist. d. veget. foss., p. 204, pi. liii. fig. 2. 



Splieiwpteris obtusiloba, Zeiller, Flore foss. d. bassin houill. d. Valenciennes, p. 65, pi. iii. figs. 1-4; pi. iv. 



fig. 1 ; pi. v. figs. 1, 2 (exclude syn. Sph. grandifrons, Sauv.). 

 Sphenopteris irregularis, Sternb., Vers., ii. p. 63, pi. xvii. fig. 4. 

 Sphenopteris trifoliolata, Zeiller (not Artis), Flore foss. d. bassin houill. d. Valenciennes, p. 75, pi. i. 



figs. 1-4. (Ref. in part.) 



Remarks. — See notes appended to Sphenopteris trifoliolata. 



Sphenopteris mixta, Schimper. 



Sphenopteris mixta, Schimper, Traite d. paleont. veget., vol. i. p. 382, 1869. 



Sphenopteris mixta, Zeiller, Flore foss. d. bassin houill. d. Valenciennes, p. 95, pi. xii. fig. 3, 1886. 

 Sphenopteris mixta, Lesquereux, Geol. Survey of Illin., vol. iv. p. 409, pi. xv. fig. 7, 1870. 

 Sphenopteris mixta, Lesquereux, Coal Flora, vol. i. p. 276 (pi. liv. figs. 1-3 (?). 



Sphenopteris rigida (?), Lesquereux (not Brongt.), Geol. Survey of Illin., vol. ii. p. 435, pi. xxxix. figs. 5, 6. 

 Sphenopteris (Aneimioides) (?) pulchra, Marrat, Proc. Liverpool Geol. Soc, Session 13, 1871-72, p. 101, 

 pi. viii. fig. 1. 



Remarks. — In the Ravenhead Collection is a small specimen which I refer to this species. 

 It appears to be similar to the fern figured under this name by Zeiller in his Flore 

 foss. d. bassin houill. d. Valenciennes. In the description of his specimen he mentions 

 that the inferior surface of the pinnules is entirely covered with adpressed hairs. A 

 similar structure occurs on the Ravenhead example, but is on the upper surface of the 

 pinnules. 



* Carbon Flora, vol. i. p. 345, pi. xxiv. tig. 6. 



