404 PROCEEDINGS OF THE AMERICAN ACADEMY. 



or Acanthotelson, whose legs end in a sharp point. As the tracks were 

 evidently not made by any merostome, we have thought it well to refer 

 these trails to a new genus, for which we propose the name Ostrahich- 

 nites, although we are not fully persuaded that it is worth while to 

 bestow names on these tracks, except for convenience of reference. 



Arachnida. 

 Anthracomartus woodruffi Scudd. Pawtucket plant beds. (Rev. E. F. Clark.) 



Insecta. 



Mylacris Packard a Scudd. Bristol plant beds. (Rev. E. F. Clark.) 

 Etoblattina iUustris Scudd. Pawtucket plant beds. (J. H. Clark.) 

 " sp. Silver Spring, East Providence. (H. Scholfield.) 



" clarkii Scudd. Pawtucket plant beds. (Rev. E. F. Clark.) 



" scholjieldii Scudd. East Providence plant beds. (H. Scholfield.) 



" sp. Fenner's Ledge, Cranston, near Providence. (F. P. Gorliain and 



H. Scholfield). 

 " gorhami Scudd. Pawtucket plant beds. (F. P. Gorhara.) 



" exilis Scudd. From a boulder near Kettle Point, East Providence. 



(H. Scliolfield.) 

 " sp. Pawtucket plant beds. (II. Scholfield.) 



" reliqiia. Pawtucket plant beds. (F. P. Gorham.) 



Gerablattina scaptdaris Scudd. Pawtucket plant beds. (H. Scholfield.) 



" fraterna Scudd. Silver Spring, East Providence. (H. Scholfield.) 



Rhaphidiopsis dii-ersipenna Scudd. Cranston plant beds. (Rev. E. F. Clark.) 

 Paralof/us ceschnoides Scudd. Silver Spring, East Providence. (F. P. Gorham.) 



The presence of the Spirorbis and of the tracks of two marine 

 Arthropods suggest that the Rhode Island plant-beds, even if in general 

 of fresh water origin, were deposited where the sea had access to them. 

 The presence of these marine fossils, with the fresh water naiad, 

 Anthracomya arenacea, strongly suggests that the horizon of the black 

 shales of Providence and also of the red and greenish beds of Attleboro, 

 Mass., belong to the same horizon as those of the South Joggins of Nova 

 Scotia, which is Upper Carboniferous, the rocks there consisting of sand- 

 stones and dark carbonaceous shales, frequently becoming reddish. The 

 South Joggins shales also contain the remains of Anthrapaljeraon, which 

 should be looked for in the Narragansett coal measures. Thus far, then, 

 the animal remains confirm Lesquereux's reference of the dark plant-beds 

 to the Upper Coal Measures. 



These beds also appear to be higher in the series than the ]\Iiddle 

 Carboniferous Mazon Creek beds of Illinois which contain a larger 



