J. S. Diller — Bragdon Formation. 387 



Ammonitic stage sufficiently immature to show sutures of the 

 simplicity of the present example would be of a size much 

 smaller than it possesses. In my opinion, therefore, the speci- 

 men is a Glyphioceras, but the possibility should not be lost 

 sight of that it may be a young stage of a more complicated 

 and later developed type." 



We now come to the fossils found in the paste of the Brag- 

 don conglomerate. Dr. Girty identities Lithostrotion sublaeve, 

 a Baird species, from one and one-half miles east of Portugee 

 Flat, and also on O'Brien Creek, one-fourth mile below the 

 stage road. No other fossils were found at either place. 



On Hazel Creek, six miles east of Sims, there is a conglomer- 

 ate composed largely of volcanic material with but little chert 

 and therefore not typical Bragdon. It includes what look like 

 fragments of rotten calcareous sandstone which readily disin- 

 tegrates, leaving very distinct and complete impressions of 

 delicate parts of corals against the paste in such a way as to 

 indicate, as pointed out by Dr. Girty, that the fossils are in 

 place and not derived. Dr. Girty recognizes from this locality 

 Zaphrentis sp. and Loxonema sp., and the last, if not both, 

 appears to belong to the Baird. 



The only case in which there is reasonable doubt concerning 

 the relations of the fossils has already been referred to. It is 

 on Bailey Creek, where a Bragdon conglomerate contains Za- 

 jphrentis and Loxonema I in moderately soft sandstone having 

 the form of a small pebble, while there is a suggestion in the 

 arrangement of the fossils that, as on Hazel Creek, they are 

 contemporaneous, yet the evidence is not clear. If it is a peb- 

 ble, two explanations may be offered. There is the possibility 

 and perhaps probability on the one hand that the forms men- 

 tioned may have began in the Devonian, and from thence 

 have been derived, or, on the other hand, that they may not 

 be the identical forms of the Baird. 



In estimating the weight of the evidence afforded by this 

 one doubtful pebble containing more or less questionable 

 forms, it is necessary to remember that the fossils in the sand- 

 stones and shales, as well as the matrix of the Bragdon con- 

 glomerate, point definitely to the conclusion that the Bragdon 

 formation is Paleozoic and is fully in harmony with the strati- 

 graphic evidence which places the Bragdon at the base of the 

 Carboniferous section conformable beneath the Baird. 



