370 



SCIENCE. 



[N. S. Vol. XXIV. No. 612. 



the study of the fish faunas of the streams 

 of California by Professor C. H. Gilbert 

 and his colleagues showed that there had 

 formerly been some connection between 

 the Sacramento, the Coyote, the Pajaro, 

 the Salinas and various other streams that 

 are now separate. These faunal relations 

 seemed to give strong support to the theory 

 of the newness of the Golden Gate channel. 



Later study shows that the mingling of 

 these faunas may be explained otherwise. 

 During the glacial epoch the region in 

 question stood from 2,000 to 3,000 feet 

 higher than it does at present. The Bay 

 of San Francisco did not then exist, but 

 the Sacramento and Coyote drainage flowed 

 through it. Coyote Creek rising on the 

 western slope of the Mt. Hamilton range 

 flowed into the Santa Clara Valley at the 

 top of the watershed between the present 

 Coyote Creek and the Pajaro drainage. 

 An alluvial cone was built up on the flat 

 valley-floor where the Coyote emerged on 

 the plain of the Santa Clara Valley. As 

 this cone grew the Coyote swung from side 

 to side, emptying its waters now into the 

 Bay of San Francisco and now into the 

 Bay of Monterey. Fishes ascending from 

 the Sacramento into the Mt. Hamilton 

 range, could later descend into the Pajaro 

 drainage. The elevation of the coast at 

 that period carried the mouth of the Pajaro 

 farther toward the west, so that fishes could 

 pass from the Pajaro into the San 

 Lorenzo and into the Salinas without en- 

 tering the sea. 



The depression following the glacial 

 epoch submerged the mouth of the Sacra- 

 mento forming the Bay of San Francisco, 

 and separated the San Lorenzo from the 

 Pajaro and the Salinas Rivers. The de- 

 creased precipitation diminished the vol- 

 ume of Coyote Creek and it ceased to build 

 the cone near Madrone Station, and since 

 then it has flowed toward the Bay of San 



Francisco and has been cutting into its 

 alluvial cone. 



Professor Branner's paper was discussed 

 by Messrs. T. C. Hopkins, C. R. Dryer, A. 

 C. Lane, George H. Chadwick and E. 0. 

 Hovey. 



The Geology of Coon Butte, Arizona: 

 Messrs. D. M. Bareinger and B. C. 

 TiLGHMAN, Coon Buttc, Arizona. (Illus- 

 trated with diagrams and specimens and 

 presented by J. C. Branner.) 

 Coon Butte, Ariz., is a low crater-like 

 hill six miles south of Sunshine Station on 

 the Santa Fe Railway, and about twenty- 

 five miles southeast of Flagstaff. The 

 general geology of the surrounding country 

 is very simple, consisting of horizontal beds 

 of red sandstone, silicious limestone, white 

 sandstone and light brown sandstone, each 

 bed being clearly distinguished from the 

 others. In this plain is a pit about 600 

 feet deep and three quarters of a mile 

 across. The edges of the beds exposed in 

 the pit are all turned sharply upwards. 

 The slopes of the ridge around the pit are 

 covered with blocks and fragments of rocks 

 like those exposed within the pit. Several 

 years ago Mr. G. K. Gilbert made a study 

 of Coon Butte. He appears to have sup- 

 posed at first that it was formed by a meteor 

 striking the earth. His final conclusion 

 was, however, that it was caused by a steam 

 explosion. 



Some years ago a mining company acting 

 upon the theory that the Coon Butte pit 

 was made by a meteor, began a systematic 

 search for the mass in the bottom of the 

 crater-like depression. Their explorations 

 show that the region has yielded several 

 tons of meteoric iron, and that a large num-, 

 ber of pieces of this iron have been found 

 interbedded with the debris thrown from 

 the pit. The distribution of the irons on 

 the surrounding plain also lends strong 

 support to the idea that the depression was 



