288 



THE CARBONIFEROUS SYSTEM. 



In a longitudinal section the cells are seen to rise vertically, and then 

 suddenly curve to the surface, increasing at the same time in diameter, 

 and having near the aperture a few thin transverse plates. It is 

 perhaps worthy of inquiry whether this may not have been a Polyzoan 

 allied to Helopora. It is very abundant at Windsor and on the Shu- 

 benacadie, subdivision (^d). 



Chaetetes tumidus (Fig. 85, S), Edwards and Haime. — I refer to this 

 common Carboniferous species, a coral very abundant at Stewiacke, and 

 occurring also at Windsor and in Cape Breton, and which a careless 

 observer might readily confound with the preceding. It is, like it, a 

 slender branching coral, but often more robust, and sometimes pre- 

 senting even rounded or papillose masses ; and in the longitudinal section 

 its tubes do not curve suddenly outwards, but turn from the centre 

 with a gentle sweep toward the surface. Externally also it has no 

 spines on the separating walls. Though I suspect that the synonymy 

 given by Edwards and Haime includes several species, I feel certain 

 that tlie present is one of them, and I have no hesitation more par- 

 ticularly in identifying it with Favosites scabra of De Koninck. All 

 these small branching corals of the Palaeozoic rocks require a thorough 

 microscopical examination. 



Crinoidea. — Though some beds of limestone on the Shubenacadie 

 at Windsor, and on the East River of Pictou, are full of crinoidal 

 fragments, more particularly the joints of the stems, no specimens 

 sufficiently complete for description have yet been found. 



MOLLUSCA. 



Polyzoa. 



Fenestella LyelU^ n. sp. (Fig. 86), coll. J. W. D., Windsor; coll. 

 Hartt, Stewiacke. — This beautiful species is very characteristic of 



Fig. 86. — Fenestella Lyelli. 



I 



(a) Natural size. {I) Portion enlarged. (c) Cells and spines in profile. 



