298 The American Geologist. November, 1905 
is described as a "dark, flaggy hornblende schist," in part 
replaced by serpentine and emery. In an earlier publica- 
tion it was described as an altered eruptive, but in this folio 
Emerson calls it an altered sediment, probably a dolomyte 
and of Lower Silurian age, lying between the Rowe and 
Savoy schists, both of which are sericite schists. Emerson 
decided that the Chester amphibolyte is a sediment because 
in the sedimentary series of Connecticut, Massachusetts and 
Vermont there are beds of dolomyte which pass into ensta- 
tite limestones and amphibolytes. Not only is emery found 
in limestones but the amphibolytes of the above mentioned 
series are derived from limestones. The Pelham gneiss* is 
exposed in long, narrow strips, extending north and south 
and lying' to the east of the Connecticut river in Pelham 
and Shuttesbury. In this gneiss are dykes of a bronzite- 
olivine rock partially altered to serpentine. 
In this monograph Emerson mentions the occurrence 
of serpentine in the Chester amphibolyte. It enters Massa- 
chusetts from Vermont and extends southwest through 
Rowe, Hampshire, Hampden, Blauford, Granville and 
Russel counties and dips below the sands of the Westfield 
plain and does not reappear. 
New Yorfe. — In 1887 Dr. Williams published a paper on 
the serpentine^ in the Onondaga salt group at Syracuse. 
The exposure was situated on James street but for many 
years has been inaccessible. It was noted in 1837 and re- 
ported to Yaunuxem, the state geologist, who regarded it as 
an aqueous deposit. Dr. Williams claims for it an igneous 
Origin;* in 1890 he published some additional proof for his 
view. 
§ In Essex county at Port Henry and Moriah, there is 
serpentine derived from an altered dolomyte and pyroxene 
limestone. A similar rock is found in Warren county. Ser- 
pentine is associated with limestone in St. Lawrence county, 
New York. 
::: Serpentine from the vicinity of New York City is 
found at Rye and New Rochelle in West Chester county, 
■■ ponograph xxix of TJ. S. G. S. by B. K. Emei son. 
t Am. Jour. Sci., 3rd Ser., vol. 34, p. 137, "The Serpentine of Syra- 
cuse. New York," by G. H. vmlliams. 
% Bull. Geol. Soc. Am., vol. i. pn. 595-600. 
;; G. P. Mekrill, "Stones for Building and Decoration." 
