igi7] FORSAITH—ALLOCTHOXOUS PEAT 191 



the method characteristic of lacustrine peat beds. Those opposing 

 this doctrine, the autocthonists, reject the idea that this represents 

 a sedimentation of plant derivatives in open water, but contend that 

 it consists of a gradual amassing of successive generations of lowland 

 plants by prostration in situ. The strata, thus exposed, were 

 preserved from decay by a permanent though concealed water sup- 

 ply, as is true and characteristic of the upper stratum of peat 

 deposits in our swamps. 



The solution of this vexatious problem, as to which of the two 

 processes is the more probable, has been attempted for the most 

 part by geologists, and naturally enough they have sought explana- 

 tion topographically. To be sure, the results obtained by numer- 

 ous investigators in this direction have furnished many valuable 

 data relative to the formation of coal beds, although many of the 

 proofs upon which their conclusions are based are open to serious 

 objection. For example, the presence of stigmarioid roots in 

 coal beds and the supporting shales has been hailed frequently as 

 valuable testimony for an autocthonous origin of the strata in which 

 such structures are found. A broader survey of the problem shows 

 that these rootlike organs are by no means conclusive ground for 

 this deduction, since they also occur quite commonly in cannel 

 coal (a type universally agreed to have been formed in open water), 

 and consequently, a statement which argues equally for either 

 process is unreliable. In this same connection it might be well to 

 mention the quality of the so-called "fire clays " usually found below 

 coal beds. Those who believe that the majority of our coal seam 

 were laid down in situ see in the material conclusive proof that this 

 inorganic layer was at one time the subsoil of swamps, owing to an 

 absence of certain minerals which, in their opinion, could have 

 disappeared in no other way than through extraction by growing 

 plants. They fail, moreover, not only to show that this chemical 

 state could not have been brought about by prolonged leaching, but 

 also to account for similar strata in regions which reveal no evi- 

 dence that they at one time supported forests. In like manner, 

 other topographical features might be shown to present similar 

 objections in favor of sedimentation or an accumulation in place, 

 but this will suffice to illustrate that megascopic investigation alone 



