PROGRESS IN THE STUDY OF ANCIENT SEDIMENTS. 7 



from the Visingo group which lies between the "Urgebirge" 

 and the Lower Palaeozoic rocks of Scandinavia. There is 

 no doubt, as has been before remarked, that Precambrian 

 fossils will be found to exist when these rocks have been 

 more fully studied, but it is very necessary, considering the 

 many occasions on which the existence of these fossils has 

 been maintained on insufficient evidence, that very con- 

 clusive evidence should be brought forward before the 

 actual discovery of Precambrian fossils is taken as generally 

 established. At present the evidence for the existence of 

 Precambrian fossils is very much in the same condition as 

 that of the discovery of human bones in palaeolithic deposits. 

 It is generally admitted that man existed in palaeolithic times 

 from evidence other than that of the bones, some of the 

 human bones that have been claimed as of palaeolithic age 

 may possibly, nay, probably, be of that age, whilst the 

 greater number of them certainly are newer, and in the 

 opinion of many competent authorities the actual proofs of 

 the palaeolithic age of any one human bone remain to be 

 given. So with Precambrian fossils, the only difference 

 being that in the case of the palaeolithic period we have 

 actual evidence of the existence of man furnished by im- 

 plements, whereas in that of the Precambrian fossils, the 

 existence of organisms in Precambrian times is inferential, 

 the great complexity of the earliest Cambrian {Olenellus) 

 fauna rendering it practically certain that earlier faunas ex- 

 isted on the earth. It will be remembered that in addition 

 to the case described by Wiman, the existence of Precam- 

 brian fossils has been recently asserted in the phyllades of St. 

 L6 and the Torridonian of the Scottish Highlands. The 

 fossils stated to occur in the latter beds have not yet been 

 described, and, as noted in a previous article, doubt has 

 been thrown on the organic nature of those from the former. 

 Perhaps the least doubtful of the many recorded instances 

 of Precambrian fossils is that about to be noticed. I refer 

 to a paper by Noetling (9). He describes the following 

 beds in descending order : — 



4. Bhanganwalla group, or salt-crystal pseudomorph 

 zone. 



