8i2 The American Naturalist. [September, 
camptonite, the rock from this localit\- possesses [)or[)liyritic zonal 
augites with inclusions of brown hornblende crystals, similar to those 
constituting the most abundant constituent of the rock. The rock 
also possesses amygdaloidal cavities filled with calcite. The second 
locality is made known by Mr. F. L. Nason.* It is a rock-cut on the 
Rutland and Burlington R. R. near Summit, Vt. The rock is almost 
identical in appearance with dyke No. 2, of Dr. Hawes.' Prof F. 
D. Chester^ regards the serpentine of Chester Co., Pa., as having been 
derived from a bronzite-diallage rock through the alteration of the " 
bronzite to tremolite, upon its contact with a dark green hornblende. 
The original rock is of a slightly fibrous character, composed of a 
ground-ma.ss of green hornblende, diallage, a little olivine and mag- 
netite, in which are phenocrysts of bronzite prismatically elongated. 
This hornblende surrounds and includes the bronzite. In both min- 
erals, as alteration has proceeded, the original characteristics gradually 
disappear, and in their place appear those of tremolite. Enstatite- 
gabbros and gabbro-diorites are also described. The latter rock is 
thought to owe its origin to the dynamic metamorphism^ of the former. 
The rock occurring in eruptive bosses in northwestern New Jersey 
has been examined by Mr. Kemp** and found to corres^jond with 
Rosenbusch's biotite-augite-porphyrites. The plagioclastic ingredient 
is probably near anorthite in composition. Hie composition of the 
biotite is : 
SiO, AI.P3 Fe,0, CaO MgC) K/) Na.,0 Loss.- 
34-6i 15.74 8.52 tr. 20.03 17-14 tr". 2.8 
Apatite is a very abundant constituent of all specimens. The 
staurolite of a staurolite -mica-schist in the neighborhood of a mass of 
granitite, lying to the north of Saint-Etienne, France, is thought by 
Ternier » to be older than the metamorphic minerals found in the same 
rock. He believes it to be original, and in no way connected with 
the presence of the plutonic rock in its vicinitv. Tourmaline in the 
same rock owes its presence to the influence of the granitite. 
Mineralogical News.— Becker '« nropnses t<. simplify the view 
