682 abstracts: botany 



contrast with those of the Grand Canyon section and to the exposure 

 in the Mazatzal Range and Sierra Ancha of a thick series of quartz- 

 ites, shales, and conglomerates unconformably beneath the Cambrian. 



The observations presented in this paper indicate that in Cambrian 

 time a land barrier existed in the region now adjacent to Tonto Basin, 

 between the depositional basin of central and southern Arizona and 

 that now corresponding to the Arizona Plateau, or at least to that 

 part of the plateau between Payson and the Grand Canyon. It fol- 

 lows that while the whole Apache group of the Globe-Ray region and 

 its stratigraphic equivalents in eastern and southern Arizona were 

 deposited at probably about the same time as the beds of the Tonto 

 group, the beds of the two groups were probably never continuous 

 within the Tonto region of Arizona. It can not be said that any 

 particular sandstone or quartzite of the Apache group is identical with 

 the Tapeats sandstone. 



Although the evidence from fossils is lacking, it appears to be fairly 

 well established that the entire Apache group is Cambrian, or possibly 

 in part younger, and, so far as can be seen over a wide region, is con- 

 formably overlain by the Devonian, while in the northern parts of 

 the Mazatzal Range and Sierra Ancha the Paleozoic beds overlie with 

 conspicuous unconformity a series of shales, quartzites, and conglomer- 

 ates, which is probably equivalent to the Grand Canyon series. 



The marked difference in the Carboniferous sections of the two geo- 

 graphic provinces in north-central Arizona suggests that the natural 

 barrier supposed to exist in Cambrian time may have persisted in some 

 form, possibly as a submarine ridge, throughout the Paleozoic era. 



F. L. R. 



BOTANY. — Fungi of New Mexico. Paul C. Standley. Mycologia, 

 8: 142-177. 1916. 

 But little attention has been given by collectors to the lower plants 

 of New Mexico. The only previous list of fungi of the state, enume- 

 rating 46 species, was published by Prof. T. D. A. Cockerell in 1904. 

 The present paper is based chiefly on material collected by the author 

 in connection with his work upon the phanerogamic plants. Two 

 hundred and ten species are listed, 113 of which are rusts. There is 

 included a description of a new rust, Aecidium cockerellii Arthur, on 

 Chamaesaracha coronopus (Dunal) Gray. P. C. S. 



