August 26, 1898.] 



SCIENCE. 



251 



ieolites spiralis), the latter said to occur in 

 the primordial rocks of Sweden. Waleott 

 reports the discovery, in the Grand Caiion 

 of the Colorado, of the following Precam- 

 brian fossils : "A minute discinoid or 

 patelloid shell, a small Lingula-like shell, 

 a species of Hyolithus, and a fragment of 

 what appears to have been the pleural lobe 

 of the segment of a trilobite belonging to a 

 genus allied to the genus Olenellus, Olen- 

 aides, or Faradoxidss. There is also an 

 obscure Stroinato2Mra-\i'k6 form that may not 

 be organic. 



Here should be noted the discovery, in 

 1896, of Badiolaria/^' in calcareous and cherty 

 rocks of ' undoubted Precambrian age' near 

 Adelaide, Australia (Nature, Dec. 24, 1896, 

 p. 192) ; the detection of fossils in the 

 Archean of Brittany, and of three veins of 

 anthracite ' in crystalline schists of Archean 

 age' in Ecuador. 



At St. John, ISTew Brunswick, that able 

 and experienced geologist. Dr. Gr. F. 

 Matthew, has detected fossils in strata 

 ■which he refers to the upper Laurentian. 

 They occur in three horizons. The lowest 

 series is composed of a quartzite containing 

 fragments of the skeleton of hexactinellid 

 sponges allied to Cyathospongia. In the 

 upper limestone of the second horizon were 

 collected calcareous coral-like structures 

 resembling Stromatopora rugosa. In the third 

 and uppermost horizon, consisting of beds 

 of graphite, occurred great numbers of 

 spicules of apparently hexactinellid sponges. 

 " Between this upper Laurentian system 

 and the basal Cambrian occurs," says 



concretion striated by pressure. I have found similar 

 objects] in the Etcheminian olive gray beds below the 

 St. John group.'' 



*Dr. Mattheve likewise informs me: "The 

 {Badiolarian'!) rocks of Adelaide, South Australia, 

 Mr. Howchin writes to me he now finds to be Lower 

 Cambrian. He has found Arohseooyathus in them ; 

 but this is not proof of Lowest Cambrian, as the 

 genus is found in the Paradoxidcs beds of the south 

 of France." 



Matthew, "a third system, the Coldbrook 

 and Coastal, Huroniau, which has given 

 conglomerates to the Cambrian and has a 

 great thickness." He also tells us that the 

 Precambrian St. Etcheminian beds at St. 

 John, consisting of red and green slates 

 and shales, have a meagre fauna compris- 

 ing Protozoa, brachiopods, echinoderms, 

 molluscs, with plentiful worm burrows and 

 trails. In commenting on this subject Sir 

 J. W. Dawson remarks that these Etche- 

 minian strata rest on Huronian rocks 

 which, near Hastings, Ontario, contain 

 worm burrows, sponge-spicules, ' and lam- 

 inated forms comparable to Cryptozoon and 

 Eozoon.' (Nature, Oct. 15, 1896, p. 585.) 



Even allowing room for error in the cor- 

 relation of these formations, and in regard- 

 ing some of these rocks as no older than 

 Cambrian, yet on the whole the result ap- 

 pears to be that abundant vegetation ex- 

 isted in Precambrian times, which was 

 converted into graphite, while representa- 

 tives of seven classes were perhaps already 

 in existence previous to the Cambrian 

 period. 



The following lists give a comparative 

 view of the classes of the periods in ques- 

 tion : 



Pi-ecamhrian Classes. 

 Ehizopoda (Eadiolaria). 



Poritera ( Hexactinellid 

 Sponges). 



Actinozoa (Corals). 



Braohiopoda. 



Annelida. 



Camhrian Classes. 

 Ehizopoda ( Foraminif era 



and Eadiolaria). 

 Porifera (Sponges). 

 Hydrozoa (Meduse and 



Graptolites). 

 Actinozoa (Corals). 

 Braohiopoda. 

 Annelida. 

 Crinoidea. 

 Asteroidea. 

 Lamellibranohiata. 

 Gastropoda (including 



Pteropoda* ) . 

 ? Cephalopoda (Ortho- 



ceras ? ) . 



Trilobita. Trilobita. 



Crustacea. 



* Dr. Matthew writes me that he doubts if Hya- 

 lithoid shells should be referred to Pteropoda. " Pel- 

 seneer quite repudiates them ; and to me their heavy 

 shells, and frequent habitat on rough shores, do not 

 speak of the fragile Pteropoda." 



