142 PROCEEDINGS OF THE ACADEMY OF [1895. 



ous green sands found suitable conditions of life. Although these 

 changes were such as to build up very heavy deposits of each class, 

 it would appear as if none of them continued long enough to enable 

 the contained plant life to accumulate a sufficiently large growth to 

 form anything beyond the merest trace of lignite. 



During the whole of this period only some seven or eight seams of 

 lignite have been laid down, and even these, with the exception of 

 one, do not exceed two feet. In the first 200 feet, including the 

 whole of the Hatchetigbee section and uppermost 30 feet of the 

 Woods Bluff, no lignite occurs. Below this we have some 25 

 feet with thin beds. Of the 140 feet forming the Bells Landing 

 stage only five feet of lignite are found, and these occur in three 

 seams, the upper one of which is 2 feet thick and lies some 75 or SO 

 feet above the other two, which are only from 6 to 8 feet apart. The 

 next lower or Nanafalia section shows 200 feet of gray sandy clays 

 and cross bedded sand and glauconitic sands and clays with green 

 sands containing Gryphcea thirscE. About ten feet above the base, a 

 hed of lignite from 4 to 7 feet thick occurs and this is the only lignite 

 seen in that series. 



Throughout the Texas areas the lignite beds everywhere form 

 conspicuous objects in this horizon, although no attempts have yet 

 heen made to correlate them with each other. 



These beds apparently represent a period when the whole coast 

 was made up of swamps, lagoons and bayous, the extent of which 

 will be best understood when we say that these deposits cover an 

 area extending nearly 170 miles from north to south and 200 miles 

 from east to west within the limits of East Texas alone. A rank 

 vegetation grew on the marshy portions, and the rivers of the time 

 having no fixed channels, distributed their waters through the 

 lagoons and bayous, and into them and over the low islands carried 

 their burdens of debris during periods of flood. With this debris 

 came soft clay, sand, branches, limbs and trunks of trees, all of 

 which went to swell the accumulations already gathering and aid in 

 the formation of the lignites and associated beds of clay and sand. 

 It is more than probable, however, that the lignites were largely 

 formed from marine vegetation which grew where these deposits are 

 now found. The Texas lignites are remarkably free from clay, and 

 although trunks of trees, both in a lignitized and silicified form occur 

 in them they are by no means numerous and are exceedingly few 



