246 J. D. Dana — Lower Silurian Fossils 



near the east side ; and they render probable, if not certain, 

 the overlying position of the schist in this ridge. 



Bat the fossils above mentioned are not those of the speci- 

 men of limestone received from Mr. D. Clark. That specimen 

 was given him by Mr. J. W. Smith, of Canaan-4-Corners, and 

 came from the' farm of Mr. E. S. Hall above referred to. Un- 

 fortunately, all that is now exposed to view is in three loose 

 angular masses, two feet in cubic size and smaller, and not a 

 ledge. 



A fourth larger mass was till recently in sight ; but it has 

 had its upper part removed to a considerable depth below the 

 suface in clearing the farm of its rocks, and I was informed by 

 Mr. Smith, that in the removal two wagon loads of blocks were 

 carried off, though, a large portion was left under the soil. 

 As the farm was under cultivation through the season, I 

 could not have an opening made. An attempt to find the 

 underground mass made since I left the region has proved un- 

 successful ; so that it will have to remain undiscovered until 

 another season opens. As to the origin of the four masses, all 

 I can say now is that, if transported, they are not probably from 

 any point outside of the valley; for they are angular masses, 

 little worn, and lie all within fifty feet of one another. As the 

 rock is a porous one, it would wear more easily than other por- 

 tions of the limestone and hence be likely to be covered with 

 soil. 



Although the evidence from these specimens is not yet avail- 

 able because of the doubt as to locality, it is of interest to note 

 that they are almost identical in character with the fossiliferous 

 Wappinger valley limestone (part of Emmons's Western Taconic 

 limestone) at Pleasant Valley, a few miles northeast of Pough- 

 keepsie. Like that, it consists largely of nodules of so-called 

 Chceletes compactus (now shown by Mr. Dwight to be a Soleno- 

 pora), which give it the aspect of a conglomerate. Along with 

 this fossil, the eye easily detects disks of crinoids, true Chsetetes, 

 and in one case a portion of a large Receptaculites, similar to 

 that found with the same limestone at Rochdale near Pough- 

 keepsie. Prof. Dwight has made slices of the rock and says 

 that it contains all of the kinds of fossils occurring in the 

 Pleasant Valley limestone, and others observed by him only 

 at other localities in that region. There is no doubt of its 

 Trenton age. 



In former papers I have presented evidence, gathered by my- 

 self and earlier observers, proving that the Taconic range and 

 the adjoining limestones on the east and west, constitute, in 

 the main, a great synclinal or compound synclinal. It hence 

 follows that fossils of the western limestone of Canaan indicate 

 the Lower Silurian age of the eastern or Stockbridge limestone. 



