1892. J NEW-YORK MICROSCOPICAL SOCIETY. 61 



traversed by spring branches, the formed earth carrying a large 

 proportion of vegetable debris. 



"Five slides illustrating vegetable or plant structure in Ala- 

 bama coal ; all of the specimens being derived from a non- 

 coking, semi-bituminous coal from the Deer Creek coal vein^ 

 Walker Co., Ala, This variety of coal burns quietly, without 

 bituminous intumescence, thus leaving foliated plates of a whitish 

 shale, which can be readily separated into thin pellicles, and 

 from these pellicles there can be isolated two specific kinds of 

 vegetable structures, derived from stems, branches, or trunks of 

 coal-forming plants ; and a third kind of vegetable structure, 

 shown in tlide labelled ' Fossil Sporangia.' When isolated from the 

 burned coal shale in their unbroken state, they are very minute, 

 oval, scale-like porcelain plates, having a collapsed appearance, 

 and when first enclosed in balsam show numerous dark annular 

 spaces which become semi-transparent rings when the air is ex- 

 pelled from the sporangium. These minute bodies may be con- 

 strued as a key to one of the associated phenomena of the 

 formation of coal strata in geologic time, in this wise : they aid 

 in proving that coal is a sedimentary aggregation of microscopic 

 plant particles, in connection with larger or grosser vegetable 

 particles, readily visible to the eye, such as the seal-like impres- 

 sions of Sigillaria stems, the fossil ' charcoal ' commonly seen on 

 the deposition layers of the bituminous coals of Alabama, and in 

 the pyritized shales occurring interbedded in the coal, which show 

 clearly vegetable structure in profusion, but of little structural' 

 interest under the microscope. An analogy between the forma- 

 tion of coal strata, recent marine muds, and fossil diatomaceous 

 strata has, by the discovery of the fossil sporangia in coal, been 

 suggested to me, in this sense: that in all preliminary cleanings of 

 Mobile Bay marine muds, of the marsh muds, and of the several 

 fresh-water fossil diatomaceous earths recently examined by me, 

 there is a moderate proportion of vegetable debris of plant 

 tissues, but more particularly and invariably an abundance of 

 coniferous or pine-pollen grains, which are of such a special 

 bilobated structure as not to be readily confounded with any 

 other organic structures, vegetable or mineral; and as these pine- 

 pollen grains are abundant in the Montgomery, Ala., diatoma- 

 ceous earth, which is also exceedingly rich in fresh-water diatoms,. 



