232 C D. WALCOTT PRE-CAMBRIAN FOSSILIFEROUS FORMATIONS 



of beds (Etcheminian) below tbe Saint John terrane which contain a 

 fauna that may be pre-Camhrian.* He correlates the " Etcheminian " 

 rocks of the Hanford Brook section with certain red and green sediments 

 on Random sound, Trinity ba3^ Newfoundland, which occur above the 

 great unconformity ])et\veen the Avalon terrane and the Cambrian in 

 other localities on the Avalon peninsula. 



Mr Matthew writes me, under date of January, 1899, that the evideJice 

 of unconformity between the Etcheminian rocks at Random sound and 

 the superjacent Cambrian rocks is that the two series have a different 

 dip, and that the latter have a conglomerate at the base, made up at 

 one locality of fragments of the Etcheminian rocks and at another of 

 fragments of the pre-Etcheminian rocks. He states further that at Han- 

 ford brook the non-conformity is not very apparent, but that west and 

 north of Saint John the Etcheminian is entirely eroded and the Saint 

 John Cambrian beds rest directly on the Huronian and Laurentian ; 

 ■further, that the Etcheminian, although separated from the Cambrian, is 

 in near relation to it and the fauna is still Paleozoic. 



Mr Matthew has recently written me that he is now preparing a de- 

 tailed description of the Etcheminian rocks and their contained fossils, 

 which will give the data showing the relations of the Etcheminian fauna 

 to that of the Cambrian. 



In a preliminary note he states that the fauna consists of about 20 

 species. t No traces of trilobites have been found. 



" Various forms of the family Hyolithidie are the dominant types. Other gas- 

 teropoda allied to Capulus and Platj^ceras occur ; also brachiopods ; remains of 

 echinoderms (cystids?), and corals allied to Archseocythus and Dictyocyathns. 

 The thin limestones which occur in the upper half of the terrane are supposed to 

 have originated chiefly from foraminifera (Globigerina, etc.)" 



The supposed fossils described by Mr Matthew from the Laurentian 

 rocks of New Brunswick | are probably of inorganic origin, as stated by 

 Dr RaufF.g 



ARIZONA GRAND CANYON SERIES 



Fossils. — The traces of life in the Grand Canyon series consist of a few 

 small fossils found in the upper division of the Chuar terrane, and a 

 Stromatopora-like form from the upper portion of the lower division 

 and the central portion of the upper division of the Chuar. 



I sent the Stromotapora-like form to Sir William Dawson, who very 

 kindly made a study of it. He was not at all sure that it was a fossil, 



*Loc. cit, p. 109. 



t Amer. Geol., vol. xxii, 1808, p. 252. 



J Bull. no. 9, Nat. Hist. Soc. New Brunswick, pp. 42-45. 



g Neues Jahrbuch Min. Geol. and Pal., 1893, pp. 57-67. 



