TRANSACTIONS OF SECTION C. 749 



quoted as evidence of rapid elongation, of little or no pliysiological significance. 

 Abundance of secretory tissue. Anatomical characteristics of a Lepidodendroid type 

 of stem ; great development of secondary tissue in the outer cortex, little or no true 

 cork, lax inner cortex. Lacunar tissue in the roots of calamites; hollow appen- 

 dages of Stif/))iaria. Indications of xerophytic characters may be the result of 

 growth in salt marshes. 



Evidence as to the Manner of Formation of Coal. 



(a) The structure of calcareous nodules found in coal seams ; the preservation 

 of delicate tissues, the occurrence of fungal hyphse and the petrification of Stig- 

 marian appendages as evidence in favour of the subaqueous accumulation of the 

 plant-debris found in the calcareous nodules. 



{b) Ordinary co«/ microscopically examined. Spores, fragments of tissues, bac- 

 teria, and the ground substance of coal. Coal found in the cavities of cells in 

 carbonised tissues. Suggested non-vegetable origin of the matrix of coal. 

 * Boulders' and coal-balls included in coal seams. 



(c) Boghead, Cannel coal, and Oil-shales. — Recent investigations of Bertrand, 

 Renault, and others. The structure and mode of origin of torbani^e, kerosene, 

 shale, &c. Suggested origin of Boghead from the minute bodies of algae {fleurs 

 d'eaii), spores, &c., embedded iu a brown ulmic substance found on the floor of a 

 lake. Absence of clastic material. Cannel coal characterised by abundance of 

 spores. 



{d) Paper-coal of Russia. — The paper-coal of Culm age in the Moscow basin con- 

 sists largely of the cuticles of a Lepidodendroid plant, Bacterial action as an agent 

 in the destruction of plants and as a factor in the production of coal. 



The Origin of Coal. By J. E. Maer, F.R.S. 



L Mhat is Coal? A non-scientific term introduced into scientific nomen- 

 clature for substances of divers character and, therefore, probably of different 

 modes of origin. 



II. Was the Carboniferous jjeriod one where conditions suitable to formation of 

 coal were unusually widespread ? 



Coincidence at this period of dominant giant cryptogams, extensive plains of 

 sedimentation, and suitable climatic conditions. Such coincidence never occurred 

 before or after the Carboniferous period. 



III. What work should be done in order to advance our knowledge of origin of 

 coalf 



In the past light has been thrown on coal-formation by chemical, petroloo-ical, 

 pala3ontological, and stratigraphical studies, and these should be continued. 



1. Chemical. — Importance of study of chemical composition of fire-clays and 

 other accompaniments of coal in addition to coal itself. 



2. Petrological. — Dr. Sorby's work on origin of grains of mechanically formed 

 rocks (sandstones, &c.) should be continued. 



3. Talceontoloyical. — Studies of faunas and floras throwing light on physical 

 and also on climatic conditions. 



4. Stratigraphical. — Much detailed work is required in many parts of the world 

 to discover over what periods coal-formation occurred in exceptional amount. 

 Tendency at outset to refer all upper Palaeozoic coal-formations to the Coal- 

 measures. 



The following Papers and Reports were read: — 



1. On the Fish Fauna of the Yorkshire Coalfields. 



SiJ Ed'gar D. Wellb'urn, F.G.S. 



'..1,1... 

 , , Only Lower and Middle Measures 'p'r'e'seuf ; their extent and bbundariea. 

 Lower ile'asures, tlieir esteat and general' characters, beds of marine aud fresh- 



