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grained hornblendic variety north of Linmere in the southern 

 part of Peabody, and very locally at several points in Salem, 

 Swampscott, and Marblehead. A stratified hornblendic granite, 

 or gneiss, occurs to a limited extent among the other stratified 

 rocks in Reading, conforming with them in dip and strike. In 

 Peabody, on the Newburyport turnpike north of Locust Dale 

 and near the Danvers line, Prof. Hyatt has observed a granitoid 

 gneiss, apparently conformably interstratified with the horn- 

 blende slate occurring there. This is probably a true gneiss. 

 The typical granite along the Eastern Railroad in Rowley, and in 

 Newbury south of the river Parker, presents a coarse but im- 

 perfect gneissic structure at several points. I observed the 

 strike in one place to be N. 60° W., dip vertical. Portions of 

 the granite on the west side of Hospital Point, in Beverly, have 

 a peculiar schistose structure ; the constituent minerals, es- 

 pecially the quartz, appearing not as grains or crystals, but as 

 small lenticular sheets, lying in parallel planes. This appears 

 to be the granulite of the books ; strike, north-west. Granite 

 possessing a more normal gneissic structure also occurs in this 

 locality. In Arlington, north-west of Spy Pond, there is some 

 stratified granite, or granitoid gneiss ; the bedding is quite 

 distinct at some points ; strike, north-east. A rock similar to 

 the stratified granite of Rowley is exposed in the railroad cut 

 at Natick, east of the station, and appears, in part, to be inter- 

 calated with the hornblende slate and diorite. In the north- 

 eastern part of Dover, near Mill Brook, Mr. F. W. Very has 

 observed an interesting series of stratified hornblendic and 

 petrosilicious rocks, some of the latter of which approximate to 

 the euritic variety of granite. The average strike is north- 

 south. Most of the rock on the Cohasset shore, between Little 

 Harbor and Black Rock, is a little quartzose gneiss, which, 

 to the general view at least, does not seem to be wholly 

 foreign to the surrounding granite, but has the appear- 

 ance, rather, of being a portion of the granite which still 

 retains a trace of the structure that originally characterized the 

 whole. The strike is quite constant, and averages about north- 



