74 Geological Society : — 



its associated rock-masses present identical features, from which the 

 authors deduced the following generalized section : — 



The underlying basalt gradually passes upwards into a variegated 

 lithomarge of about 30 feet thick, graduating insensibly into a red 

 or yellow ochre or bole of about 5-6 feet in thickness, which passes 

 into a dense red ochreous mass of about 2 feet, charged with ferru- 

 ginous spheroids consisting chiefly of a protoxide and peroxide. The 

 spheroids are of the average size of peas ; they increase in number 

 and size towards the upper part of the band, and not unfrequently 

 constitute that portion of it. The line of junction between the iron 

 band and the overlying and usually more or less columnar basalt 

 is in all cases well defined, and in a few instances exhibits decided 

 unconformability. 



The authors discussed the several theories that may be sug- 

 gested to account for the origin of the present condition of the piso- 

 litic ore, and proceeded to point out what appeared to have been the 

 several stages of metamorphic action by which the pisolitic ore had 

 been elaborated out of basalt. Prom field observations and chemical 

 analyses, they have been led to consider the bole and lithomarge to 

 be the resultants of aqueous action in combination with acidulated 

 gases, which, dissolving out certain mineral substances, has effected 

 the decomposition of the basalts, — and to assume that the bole 

 underlying the iron band was a wet terrestrial surface, and that the 

 subsequent outflow of basalt effected, by its heat, pressure, and 

 evolved gases, a reduction of the contained oxides of iron into the 

 more concentrated form in which they occur in the pisolite, the 

 aggregation of the ferruginous particles being a result of the same 

 actions. 



The ferruginous series, with interstratified plant-beds, at Bally - 

 palidy was next described, and demonstrated to be of sedimentary 

 origin — the ferruginous conglomerate resulting from the degrada- 

 tion of the pisolitic ore, of which it is chiefly reconstructed, and of 

 the underlying ochres. 



Many additions were made to the list of plant-remains from 

 these beds ; and priority of discovery of plants in the Antrim basalts 

 was accorded to Dr. Bryce, E.G.S. 



2. " Notes on the Structure of SigiUaria" By Principal Dawson, 

 F.R.S., F.G.S., Montreal. 



In this paper the author criticised the statements of Mr. Car- 

 ruthers on the structure of JSigiltaria (see Q,. J". G. S. xxv. p. 248). 

 He remarked that Sigillaria, as evidenced by his specimens, is not 

 coniferous ; that the coniferous trunks found in the Coal-formation 

 of Nova Scotia do not present discigerous tissue of the same type as 

 that of SigiUaria; that iio Conifer has a slender woody axis sur- 

 rounded by an enormously thick bark; that Ocdamodendron was 

 probably a Gymnosperm, and allied to SigiUaria ; that although 

 Stigmaria may not always show medullary rays, the distinct sepa- 

 ration of the wood into wedges is an evidence of their having ex- 



