a90 R. KIDSTON ON THE FRUCTIFICATION 
40. On the Fructirication of ZEILLERIA (SPHENOPTERIS) DELICATULA, 
Sternb., sp.; wth Remarks on URNATOPTERIS (SPHENOPTERIS) 
TENELLA, Brongt., and HyMENoPHYLLITES (SPHENOPTERIS) QUAD- 
RIpactYLites, Gutbier, sp. By Rosert Kinston, Esq., F.G.S. 
(Read May 28, 1884.) 
[Prats XXV.| 
So much confusion has arisen between Sphenopteris delicatula, 
Sternb., Sphenopteris tenella, Brongt., and Sphenopteris quadridacty- 
lites, Gutbier, that in dealing with Sphenopteris delicatula, Sternb., 
it is also necessary to give a list of the synonyms of the two other 
species, which, in the barren condition, approach it somewhat 
closely. 
The small-pinnuled members of the genus Sphenopteris, Brongt., 
are, under the most favourable circumstances, from the delicate nature 
of their fronds, extremely difficult to determine. As they usually 
occur in avery fragmentary condition, and the segmentation of their 
pinnules varies considerably according to the position held by the 
pinne on the frond (the pinnules of the upper pinnz being generally 
more simple than those on the lower pinnz), the difficulty of diseri- 
minating the species is considerably increased. 
When the specimens have suffered any lengthened maceration, 
the limb of the pinnules usually disappears entirely, and there is 
nothing but the veins left. In this state, the specific identification 
of these delicate Sphenopteroids is very unsatisfactory, if not quite 
useless. 
Fortunately the fruit of Sphenopteris delicatula, Sternb., Spheno- 
pteris tenella, Brongt., and Sphenopteris quadridactylites, Gutbier, 
is known ; and though their barren fronds may possess a considerable 
likeness, their fructification is very distinct; but even the barren 
fronds, when well preserved, are sufficiently marked to enable one 
to determine the species with absolute certainty. 
ZEILLERIA, NOV. gen. 
Involucres borne at the extremities of the pinnule-segments, 
which are more or less produced to form a pedicel; in the earlier 
condition the involucres are globular, but at maturity they split into 
four valves. 
The ferns for which this genus is proposed have been included 
by Stur, in his last work on the classification of Carboniferous 
Fossil Ferns*, in his genus Calymmatotheca; but from the ferns 
originally placed by him in this genus they differ so materially in 
certain structural points that it is necessary to place them in a new 
genus. 
* Stur, “ Zur Morph. u. Syst. der Oulm- u. Carbonfarne,” Sitzb, der k. Akad, 
d. Wiss. in Wien, vol. lxxxviii. Abth. i. p. 799 (1888). 
