On Sigillaria, Stigtmria, and Neuropieris. 373 



this, together with the circumstances of one individual stem having its 

 libs wide at the base, as in >S'. reniformis^ and narrow at the top, as in 

 S, pachyderma^ and the petiole scars in close contact, as in Favularia tcs^ 

 sellata (Fossil Flora, pi. 75), it is maintained, has led to the establish- 

 ment of a number of factitious species, and even genera. 



Respecting the fluted character of Sigillaria, the opinion is advanced, 

 that it is due to a peculiar arrangement of the leaves on the stem, or, in 

 other words, that it arises from a slight modification of the law which pro- 

 duces the rude channcllings on young branches of some Conifers, rather 

 than to the cause which produces the more obvious furrows of certain 

 Cactuses, if, as Brongniart appears to think, the furrows of the latter plants 

 result from the corresponding character on their ligneous cylinder. 



In working out the foliage of this plant, an examination is first made 

 of the various leaves which have been found in the coal-measures. Of 

 these, it is concluded, that Pecopteris and Neuropteris, the one or the other, 

 from their abundance and other circumstances, possess the strongest 

 claims to be considered as having belonged to Sigillaria. The inquiry is 

 next entered upon as to which of these fossils is the one to be so corre- 

 lated ; an inquiry which, it will be evident, ought to be influenced, to a 

 certain extent, by the discovery of Brongniart, that Sigillaria is allied both 

 to the Ferns and to the Cycases, because, it seems to follow, that if the 

 trunk shewed its situation to be intermediate to the last two tribes, so 

 the leaves should possess the like character. Now, as Pecopteris is a 

 normal fern, and Neuropteris an abnormal one, in some respects, and as 

 the last bears the closest afiinity to Odontopteris, a genus which gradually 

 conducts us to the Cycadeous type, that is, of the Jurassic period — througli 

 certain species of Otopteris, the conclusion is drawn, that Neuropteris con- 

 stituted the foliage of Sigillana, This inference, it is maintained, is fur- 

 ther supported by the relative geological ages of these foliaceous remains. 



Respecting the root of Sigillaria, this is shewn to be Stigmaria.* 



By an examination of the dome- shaped specimen figured in the preface 

 to the 2d vol. of the Fossil Flora (P. xiii.), and preserved in the New- 

 castle Museum, the error is corrected, that it exhibits "^ the upper sur- 



* Mr King announced this opinion at a meeting of the Natural History So- 

 ciety of Northumberland, Durham, and Newcastle-upon-Tyne, on May 23, 

 1842 {vide Literary Gazette, 1842, p. 425); and in May 17, 1841, previously 

 to examining all the evidence bearing upon the question, he read an account of 

 a specimen of Sigillaria, belonging to the Newcastle Museum, and adverted at the 

 same time to some characters occurring on the base of this fossil, " apparently 

 leading to the conclusion, that Stigmaria is the root of Sigillaria." 



From a notice in the Athenaum of August 20, p. 772, it appears that Mr 

 King's opinion has been completely confirmed by the discovery of Mr Binney 

 of an upright Sigillaria, nine feet high, in the coal strata at St Helen's, near 

 Liverpool, having the roots remaining, which are the undoubted Stigmaria 

 ficoides. 



