XIII.] GEOGNOSY OF THE APPALACHIANS. 249 



an outcrop of rocks of tlie second series. To the southeast of 

 the White Mountains, along our line of section, the same 

 mica-schists and gneisses, often with very moderate dips, ex- 

 tend as far as Portland, Maine, where they are interrupted by 

 the outcropping of greenish chloritic and chromiferous schists, 

 in nearly vertical beds, which appear to belong to the second 

 series. 



I find that the strata of the second series appear from be- 

 neath the Carboniferous at Newport, Ehode Island, in a nearly 

 vertical attitude, and are also seen in the vicinity of Boston 

 and Brighton, Saugus and Lynnfield. Their relations in this 

 region to the gneisses with crystalline limestones of Chelms- 

 ford, etc., which I have referred to the Laurentian series,* 

 have yet to be determined. 



We have already mentioned that the crystalline rocks of 

 Pennsylvania pass into Maryland and Virginia, where, as H. D. 

 Eogers informs us, they appear in the mountains of the Blue 

 Eidge. It remains to be seen whether the three types which 

 we have pointed out in Pennsylvania are to be recognized in 

 this region. A great belt of crystalline schists extends from 

 Virginia through North and South Carolina, and into eastern 

 Tennessee, where, according to Safford, these rocks underlie 

 the Potsdam. It is easy, from the reports of Lieber on the 

 geology of South Carolina, to recognize in this State the two 

 types of the Green Mountain and White Mountain series. 

 The former, as described by him, consists of talcose, chloritic, 

 and epidotic schists, with diorites, steatites, actinolite-rock, and 

 serpentines. It may be noted that he still adheres to the 

 notion of the eruptive origin of the last three rocks, which the 

 observations of Emmons, Logan, and myself in the Green 

 Mountains have shown to be untenable. These rocks in South 

 Carolina generally dip at very high angles. The great gneissic 

 area of Anderson and Abbeville districts is described by Lieber 

 as consisting of fine-grained gray gneisses with micaceous and 

 hornblendic schists, and is cut by numerous veins of pegmatite, 

 holding garnet, tourmaline, and beryl. These rocks, which 



* American Journal of Science (2), XLIX. 75. 

 11* 



