1"1 PROCEEDINGS OP Till: AMERICAN ACADEMY. 



or Acanthotelson, whose l''_ r - end in a Bharp point, As the tracks were 

 evidently not made by any nx-i-i^tnine, we have thought it well t<> refer 

 tin-.' trails to a new genua, for which we propose the name Ottrakich- 

 nit's, although we are not fully persuaded that it i> worth while to 

 <w names on these tracks, except for convenience of reference. 



ARA< HMD \. 

 .1 thracomarttu woodruffi Scudd. Pawtucket plant beds. (Rev. E. V. Clark.) 



I\-i l I v. 



Mylacris packardii Scudd. Bristol plant beds. (Rev. K. P. Clark.) 

 Etobhiitina i t S 1. Pawtucket plant in-'!*. (J. 11. t'lark.) 



" sp. Silver Spring Providence. (H. Scholfleld.) 



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

 " scholjieldii Scudd. Bast Providence plant beds. (II Scholfleld.) 



" s/>. Penner's Ledge, Cranston, near Providence. (F. 1'. Gorliam ami 



II. Scholfleld). 

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



exilis Scudd. From a l>oulik-r Dear Kettle Point, East Providence. 



(II. Scholfleld.) 

 sp. Pawtucket plant beds. 11 Scholfleld.) 

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



ttina scapularis Scudd. Pawtucket plant beds. ill. Scholfleld.) 

 " fraterna Scudd. Silver Spring, East Providence. (II Scholfleld i 



Rhaphidiopsis diversipenna SeixM. Cranston plant beds. (Rev. E. F. < "I irk.) 

 Parcdogus ceschnoides Scudd. Silver Spring, Easl Providence. (F. P. Gorham.) 



The presence of the Spirorbis and of the tracks <>f 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 <>f the black 

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

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

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

 stones and dark carbonaceous Bhales, frequently becoming reddish. The 

 South Joggins shales also contain the remain- of Anthrapalaeraon, which 

 should be looked for in the Narragansett coal measures. Thus f;u-, 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 Beries than the Middle 

 Carboniferous blazon Creek beds of Illiuois which contain a larger 



