344 U. B. WILLIAMS — SILURIAN-DEVONIAN BOUNDARY 



Feet 



3. Dirty greenish rocks, finely ripple-marked, full of fossils. Dip, 203°< 



32° 205 



4. Dirty green and gray, rubbly or prismatic, rusty weathering argillo- 



arenaceous flags ; the bottom of Doctor Honeyman's group D — Lower 

 Helderberg or Ludlow Tilestone (Quarterly Journal of the Geological 

 Society of London, 1864). Dip, 194°<38° 393 



5. Indian red crumbly prismatic marl, with a thin band of gray limestone 



full of fossils ; in the upper part mixed with bright green patches and 

 full of calcareous nodules, like the rock of Indian brook, cape George. 

 The green of the beds immediately overlying is brighter than usual, 

 and the whole mass is more or less concretionary and nodular. This 

 is Doctor Honeyman's "red stratum" (op. cit., p. 336), and is also 

 described in Mr Weston's section and shown in view number 6. Dip, 

 169°<34°, It has been traced more than half a mile eastward of the 

 Trunk road 30 



The classification of the rocks of the whole Arisaig section is as follows : 



E 8 Lower Helderberg = division D of Doctor Honeyman = Upper Ludlow Tile- 

 stone. 

 E 3 Niagara = C " =Aymestry limestone. 



E2 j Upper Clinton B» | = ^ LvL6Xovim 



1 Lower Clinton B " * 



E 1 Medina = A " = May hill sandstone. 



(p. 37P). 



The part of the section given above constitutes division E 6 , Lower 

 Helderberg, of this classification. 



FIFTEEN LOWER HELDERBERG SPECIES RECOGNIZED IN ARISAIG SECTION BY 



DOCTOR AMI 



The species collected by Mr Weston from this Arisaig section in 1886 

 were identified by Doctor H. M. Ami, and a report of them is published 

 in the Proceedings of the Nova Scotian Institute in 1892.* In this list 

 15 species are Lower Helderberg species. The species of the western 

 collection described by Billings f were all collected, according to the 

 Fletcher and Faribault report (p. 48P), by Mr Weston from the upper 

 part of this formation [E 6 , Lower Helderberg], west of Stonehouse brook, 

 where fish remains were also obtained by him. They are identified as 

 of Upper Silurian age by Billings, and all the species are described as 

 new except one — Sanguinolites angulliferus? McCoy. 



The rocks for this portion of Nova Scotia succeeding the Silurian of 

 the Arisaig section were classified by Fletcher and Faribault as Devo- 



* Silurian fossils from Arisaig, Nova Scotia, by II. M. Ami (read April II, 1892), Proc. and Trans. 

 Nova Scotian Inst, of Sci., Halifax, 2d ser., vol. i, pt. i, pp. 185-192. 



f Paleozoic Fossils, vol. ii, part i. 5. On some of the fossils of the Arisaig series of rocks, Upper 

 Silurian, Nova Scotia, pp. 129, etc. 



