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"V. — On the Fructification of some Ferns from the Carboniferous Formation. 

 By Eobert Kidston, F.R.S.E., F.G.S. (Plates VIII., IX.) 



CONTENTS. 



PAGE I PAGE 



Calymmatotlieca bifida, L, & H., sp., . 140 



Soroeladus antecedens, Kidston, . .143 



Calymmatotlieca affinis, L. & H., sp., . 145 



Calymmatotlieca asteroides, Lesqx., sp., . 148 



Zeilleria Avoldensis, Stur, sp., . . .148 

 Neuropteris lieteropliylla, Brongt., . .150 

 Alcicornopteris convolida, Kidston, . .152 



Calymmatotheca, Stur, emend. 

 Kidston, Quart. Jour. Geol. Soc, vol. xl. p. 590. 



In a Review * of Dr Stur's Zur Morphologie unci Systematik der Culm- 

 und Carbonfarne,\ I pointed out that he appears to have included two types of 

 fern fructifications in his genus Calymmatotheca. 



The first type includes those forms originally placed in Calymmatotheca \ 

 and consists of a number of exannulate sporangia arranged around a common 

 point of attachment ; the second type, which was first described in Zur. Morph., 

 u. Syst. d. Culm- u. Carbonfarne.^ is there represented by C. Avoldensis and C. 

 Frenzli. The fruit of these two species is apparently surrounded by an involucre 

 or indusium, and it is only with this part of the fructification that we are at 

 present acquainted. I also further indicated that in Calymmatotheca, as I pro- 

 posed to restrict the genus, the fruiting portions of the frond are entirely 

 deprived of foliage pinnules, whereas in the other type (C. Avoldensis and C. 

 Frenzli) only a very slight modification takes place in the fertile portion of the 

 fronds — the sporangia being borne on the ordinary foliage pinnules. 



In a subsequent paper,|| when describing the fruit of Sphenopteris delicatida, 

 Sternb., 1 more fully explained the structure of such frutifications as those 

 occurring in C. Avoldensis and C. Frenzli, and for these three species 

 proposed the new genus Zeilleria. 



* Geol. Mag., Dec. III. vol. i. p. 328, July 1884. 



f Sitzb. dei' k. Akad. der Wissensch., Band lxxxviii. 1 Abth., 1883. 



% " Culm-Flora," Heft ii. p. 255, Abhandl. d. k. k. geol. Reiclisanst, vol. viii. Of the four figures of 

 Calymmatothecous fruits given here by Stur, C. Schimperi, C. minor, C. Haueri, and C. Stangeri, my 

 interpretation of the structure of these fruits is chiefly founded on C. Stangeri, as this seems the most 

 perfectly preserved. 



§ p. 799. || Quart. Jour. Geol. Soc, vol. xl. p. 590. 



VOL. XXXIII. PART I. S 



