the Horton-Windsor District, N. S. 173 



most suggestive character, as this genus makes its first 

 appearance in the Ste. Genevieve and the D. montesancB 

 Ulrich (1917) is close to the Windsor D. tenuicostiformis 

 Beede. The bryozoans afford additional evidence in their 

 Chesterian affinities. Thus Batostomella exilis (Daw- 

 son) and B. cf . abrupta Ulrich are two species, associated 

 in abundance in the Miller limestone, that are almost in- 

 distinguishable in their external and internal characters 

 from B. spinulosa and B. ahrupta Ulrich. The fenestel- 

 lid of most common occurrence, Fenestella lyelli Dawson, 

 reveals close analogies with F, elevatipora Ulrich, while 

 Septopora parva n. sp. has the small delicate zooarium of 

 8, delicatula Ulrich associated with a like arrangement 

 of accessory pores on the reverse surface. It is con- 

 cluded that the Chesterian affinities of this lower "Wind- 

 sor fauna are too strong to assign to it as low a position 

 as the St. Louis, and it is provisionally referred to the 

 Ste. Genevieve. 



Climatic correlation. — The semi-aridity characteristic 

 of Tennesseean time in Nova Scotia during the deposition 

 of the Cheverie and Windsor formations is in agreement 

 with conditions of semi-aridity in Pennsylvania during 

 Mauch Chunk time and in Michigan during the deposition 

 of the Michigan series. 



BIBLIOGEAPHY. 



Beede, J. W. — 1911. — The Carbonic fauna of the Magdalen islands. New 

 York State Mus., Bull. 149, 156-186. 



Dawson, J. W.— 1855.— Acadian geology, 1st ed.; 2d ed., 1868; 3d ed., 1878; 

 4th ed., 1891. 



Dixon, E. E. L. — 1911. — The Carboniferous succession in Gower (Glamor- 

 ganshire) with notes on its fauna and conditions of deposition. 

 Quart. Journ. Geol. Soc, London, 67, 477-567, 4 pis. 



Garwood, E. S. — 1912. — The Lower Carboniferous succession in the north- 

 west of England. Ibid._, 78, 449-586, 13 pis. 



Hartt, C. F. — 1867. — On a sub-division of the Acadian Carboniferous lime- 

 stone with a description of a section across these rocks at Windsor, 

 Nova Scotia. Can. Nat., new ser., 3, 212-224. 



Schuchert, Charles. — 1910. — Paleogeography of North America. Bull. Geol. 

 Soc. America, 20, 551. 



Ulrich, E. O. — 1917. — The formations of the Chester series in western Ken- 

 tucky and their correlates elsewhere. Kentucky Geol. Surv. and 

 U. S. Geol. Surv. (joint pub.). 



Vaughan, Arthur. — 1905. — The paleontological sequence in the Carboniferous 

 limestone of the Bristol area. Quart. Journ. Geol. Soc, London, 

 61, 181-307, 3 pis. 



— 1915. — Correlation of Dinantian and Avonian. Ibid., 71, 1-52, 7 pis. 

 White, David. — 1901. — Some paleobotanical aspects of the upper Paleozoic 



in Nova Scotia. Can. Eec. Sci., 8, 273-274. 



— 1913. — Excursion in eastern Quebec and the Maritime Provinces: 



the Horton flora. 12th Internat. Geol. Congress, Guide Book No. 

 1 (issued by the Geological Survey of Canada) , 144-146. 



