654 EEPOET— 1886. 



4. Oil recent Researches amongst the Garhoniferous Plants of Halifax. 

 By Professor W. C. Williamson, LL.I)., F.E.S. 



At the Southport meeting of the British Association a small grant was made to 

 my friend, Mr. Cash, of Halifax, and myself, in aid of our exploration of the fossil 

 flora of the Lower Carboniferous strata of Halifax and the surrounding districts. 

 Circumstances over which we had no control prevented our reporting upon the 

 results of that grant ; but since there are important reasons why those results 

 should be recorded, I now bring them before the Association in the shape of a 

 communication instead of a Report. 



The plants of the Halifax beds are much more exquisitely preserved than are 

 those of the Oldham beds of the same age. This fact has enabled us to throw 

 additional light upon the organisation of several of the plants obtained from the 

 Oldham deposits and previously described. Structures hitherto unobserved have 

 been detected, and others seen but obscurely have been made clear. 



In the dominant group of the Lycopodiacese nothing has been discovered 

 requiring us to modify our previous views respecting these plants ; and it is grati- 

 fying to know that many of our co-workers on the European Continent have now 

 materially mitigated their opposition to those views. Thus, our French fjiends, who 

 have hitherto so determinately insisted upon the Gymnospermous character of all the 

 Sigillarise, have now advanced so far as to admit the Cryptogamic and Lycopodi- 

 aceous character of the vertically grooved forms of that genus — which really means 

 most of our British forms of Sigillaria — and we have not the slightest doubt but 

 that the remaining forms will have to be surrendered to us in like manner. We 

 now have under investigation three or four Lepidodendroid branches, which appear 

 to be new, and which are awaiting their turn of publication ; we have also obtained 

 much additional information respecting the Stigmarian roots of these arborescent 

 Lycopods, which will be embodied in a monograph about to appear in the forth- 

 coming volume of the Palreontographical Society. 



Many new specimens of Calamite have been obtained, in each of which the 

 woody zone is invested by the characteristic bark previously described. They all, 

 without exception, confirm conclusions already announced, viz., that the longitudinal 

 and transverse grooves and constrictions seen in the common casts of the medullary 

 cavity of the Calamite, are entirely absent from the exterior of the cortex. Here 

 again some of our Continental friends, who have hitherto insisted upon the Gymno- 

 spermous affinities of some of the Calamites, have made an important concession to 

 our interpretation of these objects. M. Grand-Eury has now announced bis con- 

 viction that the plants which the French Palteo-botanists have hitherto included in 

 the genus Arthro2ntus are really the vascular zones of true Cryptogamic Calamites. 



Since this genus Arthropitus includes all our British specimens of which the 

 internal organisation is preserved, and since also the hypothesis of the Gymno- 

 spermous nature of the genus Arthropitus was chiefly based upon the discoveries 

 of M. Grand-Eury himself, his change of view seriously weakens the influence of 

 those who still cling to what we regard as erroneous opinions. All honour to M. 

 Grand-Eury for his courage in acting otherwise. 



Closely associated with the Calamite is the strobilus known as Calamostachys 

 Binneana, upon which our researches have thrown fresh light. In the examples 

 previously figured from the Oldham beds tbe central axis of the spike of fructifica- 

 tion appeared to consist entirely of a mass of barred vessels. But our Halifax 

 specimens have enabled us to determine that this axis consists of a solid central 

 medulla composed of parenchyma, the cells of which are somewhat elongated 

 vertically, and which is enclosed more or less completely in a thin cylinder of 

 barred and spiral vessels ; the bands of these vessels are certainly much thicker 

 along certain vertical lines than in the intermediate spaces. We have also 

 obtained a fresh example of the remarkable heterosporous form of Calamostachys 

 published in Part XII. of the 'Organisation of the Fossil Plants of tlie Coal- 

 measures,' and which latter example previously constituted the only known speci- 

 men of a Calamitinean plant with the bisexual fructification. This second 

 example seems to establish clearly the distinctness of this fructification from that 



