2o6 



PROCEEDINGS CF THE GEOLOGICAL SOCIETY. 



measures. U. Lindleyanum, U. majus, and U. minus are the Mill- 

 stone-Grit species. The above 10 genera were selected on account 

 of their being largely represented specifically. Eegarding the 

 distribution of the Carboniferous flora, we know that many species 

 occurring in Pennsylvania and Nova Scotia are identical with Euro- 

 pean and British species. This points to a greater similarity and 

 equality of climate than now prevails, and also to the possible con- 

 nexion of the coal-bearing areas of Europe with that of America, 

 either by continuous land or by groups of islands. 



It is difficult in all cases to determine from the often somewhat 

 vague descriptions of authors the true geological horizon of the 

 many species in the true Coal-measures, or whether they are 

 Upper, Middle, or Lower Coal-measure forms. Every care, however, 

 has been taken to determine this when possible, not only for the 

 Plantae but for the whole fauna also. 



Protozoa : Spongida. — The 10 genera and 15 species known 

 are confined to the Carboniferous Limestone and shales below. 

 The genus Palceacis of Haime (1860) now embraces Phillips's. 

 Hydriopora, M ; Coy's Astrceopora, Seebach's Palceacis, and the genus 

 Sphenopoterimn of Meek and Worthen. The 3 British species, 

 P. cuneiformis, J. Haime, P. cyclo stoma, Phill., and P. obtusa, Meek 

 and Worthen, have a wide geographical range, being almost uni- 

 versally distributed ; but none of the 10 genera and 15 species have 

 occurred above the Carboniferous Limestone in any area. 



Protozoa : Eoraminifera. — 14 genera (11 belonging to the Im- 

 perforate and 3 to the Perforata), with 48 species, range through the 

 lower portion of the Carboniferous group, but none have yet occurred 

 higher than the Yoredale rocks, where 7 genera and 18 species are 

 found, and only 1 genus (Stacheia) is known in the Calciferous 

 Sandstone ; 6 species illustrate Stacheia, and all range from the Cal- 

 ciferous beds to the Carboniferous Limestone. Our knowledge of 

 this order (Reticularia) of the Rhizopoda in the Carboniferous rocks is 

 due to the labours and researches of Mr. H. B. Brady. 40 species are 

 known from the Carboniferous Limestone. 43 of the 48 species in 

 these rocks are named and described by Mr. Brady in his learned 

 monograph upon the British Carboniferous and Permian Eora- 

 minifera in the volume of the Palseontographical Society for 1876. 



Hydrozoa. — Arbusculites and Palazocoryne are the only 2 known 

 genera in this class. Arbusculites argenteus, with Palceocoryne 

 radiata and P. scotica (all three from the Carboniferous Limestone), 

 complete the list. 



Actinozoa. — Both the Tabulata and Rugosa are well repre- 

 sented in the Carboniferous rocks, especially the Rugosa. 21 

 genera fall under that order, and 14 in that of the Tabulata. 

 The genus Cladochonus of M'Coy {Jania of the same author) and 

 Aulopora are the only representatives of the Tubulosa. Aulopora, 

 which is probably the young state of Syringopora, usually referred 

 to the Tubulosa, must be placed with the Tabulata if so deter- 

 mined. 9 families, 36 genera, and 141 species constitute the 

 Actinozoal fauna. The only 2 families of numerical value are the 



