Some new Foss, '^oin Eastern Massaclmsetts. — Hobbs. 113 
separation is this u conformity. The Stonybrook quartzyte 
has been found to trnderlie the Basin series, but the Kendal 
Green slate is not found, having been eroded. 
Let us turn now to the history of the region as it may be 
read from the sequence of the strata. Upon an ancient Ar- 
chaean continent situated probably to the east of the region 
studied, the Algonkian sea transgressed, gradually deepening, 
until the slate stage of deposition was reached. This condition 
seems to have prevailed for a long time, probably, if the time 
of erosion succeeding it be added to it, a time at least one-half 
as long as that from the Cambrian to the Pleistocene. It will 
probably be long a matter of uncertainty, but, comparing this 
series with the tolerably complete and legible succession of 
the Appalachian region, it is possible to see that the time ele- 
ment is great. There seems to be wanting a name for this 
older series and. if it be found to be extensive enough to war- 
rant so broad a term, the name Appalachian would be the near- 
est name of general application. There are fundamental for- 
mations throughout the extent of the Appalachian range where 
erosion has been sereve enough to expose them and it was 
doubtless folding along the same general line that tilted the 
rocks of the region here described. 
To continue with our history, having already implied a 
time of deposition succeeded by a time of erosion and eleva- 
tion, this elevation being accompanied by volcanic phenomena, 
we next come to a second submergence beneath a Cambrian 
sea, probably with the main continental mass northwest. This 
was followed by a second upheaval, also a time of volcanic ac- 
tion. Then came a depression beneath a Carboniferous sea. 
It is one of the interesting problems of this region whether 
this period of sedimentation included Triassic time. Possibly 
some of our newer diabase is an attendant upon conditions 
like those of the Connecticut Valley Triassic. This was the 
last submergence, so far as known, the Tertiary formations 
which play so important a part on the south Atlantic seaboard 
becoming reduced to a few island patches off our coast before 
finally passing from sight altogether beneath the sea. 
Summary. The principal points touched Ujion in this pa- 
])er are of course the discovery of fossil Annelida in a Pre- 
