1902.] HATCHER — OLIGOCENE AND MIOCENE DEPOSITS. 121 



or bedding were deposited in either marine or fresh waters. More- 

 over the color-bands exhibited, more especially by the clays of the 

 White River series, have been very generally mistaken for examples 

 of stratification and lamination, while true lamination in the clays 

 of this series is rare and usually of very limited extent both verti- 

 cally and horizontally. 



Dr. Matthew, in his Mejnoir already referred to, has set forth in 

 very clear and concise language the principal stratigraphic and 

 paleontologic evidences against the lacustrine theory as observed by 

 him for these deposits in northeastern Colorado. It will be the 

 chief purpose of the succeeding pages of this paper to extend these 

 observations into southeastern Wyoming and western Nebraska and 

 South Dakota, and to record some additional facts relating to the 

 stratigraphy, paleontology and paleobotany of the beds, with espe- 

 cial reference to their bearing upon the origin and mode of depo- 

 sition of the latter. 



Matthew has already called attention to the physical and topo- 

 graphical difficulticF, as well as to the lack of terraces and of certain 

 stratigraphical characters which should exist if these deposits had 

 their origin in a body of fresh water of a size comparable with that 

 outlined by Scott. These difficulties, already serious, are only 

 augmented by the increased dimensions of this lake proposed by 

 Darton. If we confine it, however, to the much more restricted 

 limits given by Dr. Scott we still have a lake of very considerable 

 dimensions, greatly exceeding in size those of any fresh-water lake 

 of modern times, with no barrier to the east or south to retain its 

 waters, without recognizable terraces about its shores, and with a 

 distribution of materials and of remains of fresh water, and of 

 terrestrial plants and animals which are at least difficult, if not 

 impossible, of explanation by the assumption of the presence of a 

 great lake. 



Character of the Materials in the White River Series. 



We have already observed, while discussing the classification of 

 the White River beds, the presence in them of frequent lenses of 

 sandstones and conglomerates. These sandstone and conglomerate 

 lenses are not arranged concentrically at varying altitudes about the 

 margins of this supposed great lake, but extend as greatly elongated 

 and narrow lenses far out into the very centre of the region which 

 this lake has been supposed to have occupied. They occur at all 



