[DAwsos] FOSSIL SPONGES AND OTHER OHGANIC REMAINS 93 



natural facts wliicli uiKlorlit! llii'tn. to (lie |>ul»liiati<)ns iiauuMl in tlio foot- 

 note to tliiw section.' 



II. — SUBDrVIHKtNS OK THE (^I'KHEC GhOUP. 



Confinin'i; ourselves to the sections on the south shore of the Lower 

 St. Lawrence, the suhdivisions, as worked out hy Loijan and ({ichardson 

 and more recently hy Iv with the aid of Whiteaves in reu;ard to the 

 Trilohites, Braehiopods, etc.. and of Lapwortli ■ and Ami in the jrrapto- 

 litie fauna, may bo stated as follows in ascending order : " 



1. The Siller !i Sm'rs, seen at the ('haudici-e liiver, near Quebec, and 

 also at Matane and Cai)e Rosier, as well as at Little M(5tis. Among its 

 characteristic fossils are the little brachio])(>d OboUila (Jjinnarssonia) 

 pretiosa. Billings, and Dictyonrnui sitcia/c of Salter {D. Jinhcllnrc of Eich- 

 wald), also s|)ecies of Bryoi/rit/ifKs and (loi>n(ir(i}>tii)^. Tiie preva'ent 

 rocks are grayish sandstones and conglomerates with shales of red, gray 

 and black colours, and more rarely bands of limestone and dohmiite. It 

 may be regarded as the base of the (Quebec Group jjroper, and as the 

 equivalert of the Calciferous of more western districlsjind of the Tremadoc 

 of Wales, and perha])s as the highest member of the Cambrian system. 



2. Tac Levin Series ; to which belong the shales, limestones and 

 conglomerates exposed at Levis, opj^osite the city of Quebec, and which 

 has been recognized as far cast as Ste. Anne des Monts. Its most iduxrac- 

 teristic fossils are graptolites of the ^-enera Fliylhxjrtiptus, Tetrui/raptus, 

 etc., most of which are described by Hall in his classical monograph on 

 this fauna ; while its Trilobites, etc.. have been studied by Billings, and 

 catalogued by Ami. who separates the fossils found in boulders in the 

 conglomerate from those ])roperly belonging to the formation.'' This 

 series is in the hoi'izon of the Upper Calciferous and Chazy, and may be 

 regarded as equivalent to the English Arenig and Skiddaw. 



3. The Marsoiiin Series ; found at that place a)id at Gritftn Cove, 

 Wliite |{iver, and elsewhere, and holding grai)tolites of the genera Diplo- 

 graptus, Ca'uocjraptus, etc. It is apparently of Chazy -Trenton age and 

 equivalent to the English Bala. 



4. Still higher beds holding Dlplograptus pristis and other forms 

 characteristic of Ihe Utica shale, and therefore newer than the Quebec 

 Grou}) proper, occur west of Marsouin River, near Tartigo Eiver and 

 elsewhere. At this period, owing to the subsidence of northern land, the 



' Appendix to Harrington's Life of Sir William Logan, p. 403 et seq. ; On the 

 Eozoi'^ and Pahieozolc Recks of Eastern Canada, .lournal London Geol. Society, 1888 ; 

 The Quebec Group of Logan, Canadian Record of Science, 1890 ; Salient Points in the 

 Science of the Earth, 1894. 



- Transactions Royal Society of Canada, 1886. 



•' For notices of previous work and recent discoveries, see Report by Ells, Geolo- 

 giciil Survey of Canada, 1887-88. 



* Report Geol. Survey of Canada, 1887-88. 



Sec. IV., 1896. 0. 



