OF SOME CARBONIFEROUS FERNS. 597 
Hymenophyllites delicatulus, Zeiller, “ Fruct. d. Fougéres Houill.” 
Ann. d. Sci. 6° ser. vol. xvi. p. 196, pl. x. f. 22-32. 
2? Sphenopteris laciniata, Gutbier, Verst. d. Zwick. Schwarzk. p. 76, 
pl. xi. f. 4; ? Unger, Syn. Plant. Foss. p. 66; Jd. Genera et 
Species, p. 122. 
Description.—Frond tripinnate; pinne alternate or opposite ; 
rachis flexuous, winged; barren fronds, pinnules divided into 4-7 
obovate lobes, which have 3-6 rounded lappets, each having a 
simple vein ; fruit borne at the extremity of the lobes; but placed 
beyond the limb. Sporangia provided with an annulus. 
Remarks.—I have already, while making a comparison between 
this species and Zeilleria delicatula, Sternb., sp., entered into all the 
details of the structure of the fruit of this fern, so far as is at present 
known, so need not repeat here what has already been said on that 
oint. 
Sphenopteris tridactylites, Geinitz (not Brongt.).—M. Zeiller has 
pointed out* that the S. quadridactylites, Geinitz, is essentially 
distinct from Brongniart’s plant of that name, and is to be referred 
to S. quadridactylites, Gutbier. The true S. tridactylites of 
Brongniart is a much more robust plant, with a firmer texture. 
That Geinitz’s figure of S. tredactylites is not Brongniart’s plant 
of that name, but is S. quadridactylites, Gutbier, will be admitted 
by any one who may examine into the subject. 
There are two other species which seem to be identical with S. quad- 
ridactylites, Gutbier. ‘These are S. opposita, Gutbier, and S. mimuta 
of the same author. — 
Sphenopteris minuta, Gutbier.—This I believe to be only the 
upper portion of a specimen of S. opposita. 
Sphenopteris opposita, Gutbier.—This I am inclined to regard as 
only a form of S. quadridactylites. It is true that in the figures of 
these two plants, the pinne are alternate in S. quadridactylites and 
opposite in S. opposita; but in many species, the pinnee are opposite 
or alternate according to the position they hold on the frond, and, 
as numerous examples show, little or no value can be placed in 
such characters as “‘ pinne opposite ” or “‘ pinne alternate” f. 
The differences between the large drawings of these two species 
(S. minuta and S. opposita), as given by Gutbier, seem to me to be 
indwidual, not specific. 
After a careful examination of the descriptions and figures to 
which I have referred, I can only regard SN. opposita, S. minuta, 
Gutbier, S. tridactylites, Geinitz (not Brongt.), and Hymenophyllites 
delicatulus, Zeiller, as belonging to Hymenophyllites (Sph.) quadro- 
dactylites, Gutbier. 
* J.c. * Fructifications de Fougéres, p. 196. 
+ Compare S. Honinghausi, Andre, Vorw. pl. iv. & pl. v. f. 1; S. acutiloba, 
Andre, Vorw. pl. vi; S. artemisiefolia, Brongt. Hist. d. Végét. Foss. pl. 
xlyi., xlvii;. S. Gravenhorstii, Brongt. Hist. pl. lv. f. 36; Neur. gigantea, 
Brongt. Hist. pl. lxix.; Pecopteris Davreuxit, Brongt. Hist. pl. lxxxviii. ;, 
Pec. arborescens (P. eyathea), Brongt. Hist. pl. ci. f. 1-2 ; Pec. arborescens, Brongt. 
Hist. pl, ci. &e. 
