354 HENRY B. KUMMEL 
few small areas southeast of the Highlands between the pre-Cambrian 
crystallines and the Mesozoic strata, (b) in narrow valleys within the 
Highlands, (c) in a board belt northwest of the Highlands, the latter 
area comprising the northern extension of the great Appalachian 
valley and the mountain west of it. 
CAMBRIAN SYSTEM 
Hardyston quartzite—The Hardyston quartzite is the lowest 
formation of the Cambrian system, and is probably to be correlated 
with the Poughquag quartzite of Dutchess County, N. Y., and the 
Chickies quartzite of Pennsylvania. It is unconformable on the 
pre-Cambrian complex and is the oldest fossiliferous rock in New 
Jersey. It varies considerably in composition and thickness. Typi- 
cally it is a quartzite, at many places conglomeratic and containing 
pebbles of quartz, feldspar, granite, gneiss, and slate. Locally the 
formation is a calcareous sandstone. It is usually but not invariably 
feldspathic. In some localities its arkose character is so marked 
that it is not readily distinguishable from a coarse granite. Beds of 
slate occur in its upper portion. 
Its thickness ranges from a few feet to 200 or more, and it passes 
into the overlying sandstone through slaty or shaly layers, several of 
which are in places interbedded with limestone layers, so that its 
upper limits are indefinite. Since it contains a species of Olenellus, 
it is regarded as of Georgian (Lower Cambrian) age. 
Kittatinny limestone—The Hardyston quartzite grades upward 
into the thick magnesian Kittatinny limestone of the Kittatinny Valley. 
Aboye, it is limited by an unconformity at the base of the Jackson- 
burg (Trenton) limestone. The presence of thin shales and scattered 
seams of sandstone in the great mass of limestone shows an influx 
of land sediments at recurrent intervals during its formation. 
The known fauna of the Kittatinny limestone is not extensive 
and is found at but few localities, but it suffices to establish the Cam- 
brian age of the greater part of the formation. No Middle Cambrian 
fossils have been found, but as the Olenellus fauna of the Hardyston 
quartzite is considered to be of Lower Cambrian age, and as no 
evidence of a break in sedimentation has been observed, a Middle 
Cambrian fauna would naturally be expected between the Olenellus 
