FORMATIONS OF CAMBRIAN AGE. 1d 
Olenelius always being the most conspicuous form. During the field 
inyestigations carried on for the preparation of the present report, 
fossils have been found (1) at various points along the line between 
Hardystonville and Frankyille Furnace, (2) at the southern end of 
lliff’s pond, north of Andover, (3) at the foot of the mountain east of 
Tranquility, (4) in the railroad cut just north of Oxford Furnace and 
(5) in the railroad cut at Washington. Aside from some more or less 
indefinite worm burrows, all of the fossils detected have been trilobites, 
referable to a single species of Olenellus, which has been identified as 
O. thompsom. Except at the localities near Franklin Furnace and 
Hardystonville, where several nearly perfect heads of Olenellus have 
been found, all of the specimens are in fragmentary condition. 
Wherever they occur the specimens of trilobites have always been found 
in the decomposed portions of the more calcareous beds of the forma- 
tions. In the process of weathering the calcareous portion of these 
beds is removed by solution, leaving a more or less friable, rusty brown 
sandstone. The tests of the trilobites are removed with the other cal- 
careous matter, leaving cavities, along which the rock easily splits; jut 
in the unweathered portions of the rock the fossils have in no ease becn 
detected, although they must be present in greater or less abundance. 
Field observations have led to the conclusion that whenever the decom- 
posed beds of the Hardyston quartzite present a rusty brown appear- 
ance, with a rather fine-grained, arenaceous texture, fragments of 
Olenellus may be detected in greater or less abundance if careful 
search is made. 
The formation occurs in the Green Pond mountain region, and 
its upper calcareous portion or the limestones immediately supecr- 
jacent to it have afforded fragments of Olenellus.* At the time of its 
deposition the formation was doubtless continuous across the present 
crystalline highlands, from the Green Pond mountain region to the 
Kittatinny valley. 
KITTATINNY LIMESTONE. 
Lying conformably upon the Hardyston quartzite there is a great 
thickness of limestone in large part dolomitic and rarely fossiliferous. 
The division between the quartzite below and this limestone is not a 
sharp one, the siliceous Hardyston beds becoming more and more 
calcareous in their composition, through strata of arenaceous lime- 
* Walcott, Am. Jour. Sci. (3), vol. XLVII., p. 309. 
