216 MESOZOir FLORAS OF rXlTHD STATKS. 



Elder Crook that Mr. Diller made his woll-knowii section," which so 

 staggered the geologists who are studying the age of the earth. Accoi'd- 

 ing to this section the Knoxville l)eds haAT a tliickness on Elder Creek 

 of 20,()(30 feet, the Horsetown l)eds of aljout (),000 feet, and the Chico 

 beds of 4,000 feet, making 30,000 feet measurcHl. And yet it seems that 

 "the complete series of the Shasta-Chico beds is not exposed in this 

 section.'"' »The strata here often approach a vertical position and the 

 section stretches across their upturned edges for a distance of nearly 8 

 miles. They consist of shales, sandstones, and conglomerates with 

 calcareous bands in the Knoxville beds. There are no indications of 

 the existence of heav,y deposits of eruptive material or other forms of 

 rapid deposition, and the faulting and folding is slight and local. Doctor 

 Stanton, who has made later and more special examiaations, thinks, 

 however, that certain facts oliserved l)y him may idtimately somewhat 

 modify these extreme results. There can l)e no doubt that those beds 

 embrace practically the whole of the Lower Cretaceous, and Doctor 

 Stanton would place the Chico beds in the Upper Cretaceous, witli their 

 lower portion on about the horizon of the Cenomanian. 



These collections reached Washington in the autumn of 1895. I 

 made a preliminaiy study of them during the winter, comparing them 

 carefully with those previously received from substantially the same 

 localities. In many cases they proved much fuller and greatly increased 

 our knowledge of the flora of those beds, but in others, as already stated, 

 Mr. Storrs and I were unable to find any additional material, and in still 

 others what we obtained was inferior in cjuantity and quality to that 

 previous!}' collected. 



Professor Fontaine was at that time engaged on other work and 

 could not undertake the determination of these collections. I had 

 planned the series of papers now in progress and, as stated in the first 

 paper, deemed it important to begin witli the lowest Mesozoic floras 

 and work up to those of the Lower Cretaceous. This plan has l^een 

 adhered to, although it necessitated the postponement of the determina- 

 tion of collections made earher than some that have l)een published. 

 The history of this work has all been fully given in its proper place. 



"Am. Jour. Sci., 3d ser., \o]. XL, December, 1890, p. 476; 15ull. (Iim.I. .Sue. America, Vol. \", 1S'.H, pp. 

 439-4-10. 



'' Bull. Geol. -Soc. Americu, Vol. V, 1894, p. 438 (footnote). 



