Section IV, 1801. [ 33 ] Trans. Eoy. Soc. Canada. 



V. — Illastraiions of the Fauna of the St. John Grouj), No. VI. 

 By Gr. F. Matthew, M.A. 



(Read May 27, 1891.) 

 (A) FAUNA OF THE BRETONIAN DIVISION (DIV. 3) OF THE ST. JOHN GROUP. 



The writer has had opportunity to complete for this article a study of ouly a part of 

 the faunas of this Division, viz. : those that belong to the Cambrian age. The later 

 Ordovician fauna will form the subject of a future communication. 



In describing these species he has taken the fossils collectively according to their 

 zoological standing, and not according to the several zones in which they occl^r, but he 

 has designated the special zone under each species. 



For reasons that will be seen in the sequel, he has substituted Zone of Parabolina 

 spinulosa {or "Zone oî Leptoplaslvs stenotoides" of his preceding paper. 



DICTYONEMA, Hall (1851). 



The earliest reference to fossils of the graptolite type, and perhaps to that species 

 which is specially the subject of this description, is that of Magnus von Bromell.' 



In his work, " Lithographise Sueconœ, specimen primum et secundum (1727)," among 

 other matters, he gives an account of a collection of fossils belonging to himself, " De 

 yegetalibus fossilibus et Japidefactis." In specimen secundum the first article bears the 

 title " De musco incrustato et in lapide depicto." He describes No. 1 as " Lapis cinerei 

 coloris fissilis fœtidus Suillus dictus in superficie ostendens musci ramosi caj^illameuta 

 nigra, subtilissimo quasi penicillo expressa, inventus in arenariis parceciae Giœrstad, prope 

 oppidem Schenningiam in Ostrogothiae." - 



The rock described by Bromell as " lapis Suillus " appears to have been anthraconite 

 or fetid limestone. " If," says TuUberg, " Bromell's description of the mineral is correct, 

 it can almost with certainty be concluded that he, by his description, meant to indicate a 

 Dictyonema. Nothing in his description forbids such a supposition. He denominates it 

 « musci ramosi capillamenta nigra,' and compares it further to a dendrite. At the same 

 time, however, he points out its dissimilarity from such forms, in that it does not pene- 

 trate the stone, but is found showing a delicate figure on the outer surface (layer) of the 

 stone only." 



' The following notes are chiefly from S. A.TuUberg's article " On the Graptolites described by Hisinger," etc. 

 See " Bihang till Kong. Svensk. Vet. Akad.," Handl. B. 6, No. 13. 



- A fissile, fetid, ash-coloured stone, called swinestone, showing on its surface black threads of a branching 

 moss, as if drawn with the most delicate pencil. Found in gravelly places (or pits) of the parish of Gierstad, near 

 tLe town of Schenning, in East Gothia. 



Sec. IV, 1891. 5. 



