252 PALEONTOLOGY OF OHIO. 



laminae is very conspicuous. The mass is traversed by numerous very 

 irregularly disposed horizontal canals which run nearly parallel with 

 the surface, have a diameter of usually from one-fifth to one-fourth of a 

 line, and are placed at intervals apart of from one-third of a line to 

 about one line. The upper surface exhibits two distinct sets of aper- 

 tures — firstly^ a series of very minute and crowded perforations, which 

 doubtless correspond with the cells of the mass ; and, secondly^ a larger 

 set of apertures, which are very irregularly distributed, and are likewise 

 very numerous. These latter apertures are circular, have a diameter of 

 from one-eighth to one-fifth of a line, are placed at intervals of from one- 

 fourth to one-half line apart, and are almost certainly the apertures of a 

 series of vertical canals. 



As regards the additional characters of the surface, the specimens 

 differ so materially that I can not with certainty affirm that they belong 

 to the same species. In the most typical examples the surface is undu- 

 lating, and exhibits numerous star-like, not elevated, impressions, formed 

 of vermicular bifurcating horizontal canals, which radiate from a central 

 point. When partially decorticated, it is seen that these radiating 

 canals have a distinct calcareous lining, and, whilst in the main hori- 

 zontal, some of them penetrate the mass obliquely, and thus pass below 

 the actual surface. THe diameter of these star-like impressions is about 

 half an inch, or rather less ; they are placed close together over the whole 

 surface. Another specimen, very much weathered, shows a smaller 

 number of the above-named stellate impressions, and also exhibits a 

 great number of small circular pits or depressions, from a line to a line 

 and a half in diameter, and placed about their own width apart. The 

 nature of these depressions could not be made out. A third example 

 (like the others, only a fragment, though of large size) exhibits a simply 

 undulated surface, with but obscure indications of any stellate impres- 

 sions. 



All the examples that I have seen of this singular species are frag- 

 mentary, and consist of flattened or undulated crusts, three or four inches 

 across, and from half an inch to one inch in thickness. It is quite prob- 

 able, however, that they are only pieces from the exterior of large spheri- 

 cal or hemispherical masses. 



It is possible that the Stromatopora constellata of Hall (Pal. N. Y., Vol. 

 II., p. 324, pi. 72, figs. 2, 2b), from the Coralline limestone of Schoharie, 

 may prove, on more minute examination, to be referable to Syringos- 

 troma; but, in any case, it is clearly distinct from the present species. 



Position and locality : Corniferous limestone, Kelley's Island, and Sandusky, Ohio. 



