2 
PALAEONTOLOGY OF NEW-YORK. 
We shall therefore commence our descriptions with those organic forms which are typical 
of the acknowledged base of the palaeozoic series on the American continent, leaving for 
future consideration those forms which have given rise to some difference of opinion 
regarding the age of the rocks in which they occur. Further explorations may add to the 
number of forms already known in this rock ; but it must be acknowledged, that, thus far, 
it has proved very barren in organic products. 
ORGANIC REMAINS OF THE POTSDAM SANDSTONE. 
Plate I. 
Genus S COL IT HUS. 
[From the Greek, tfxwXiig, a worm, and Xidos, a stone.] 
Skolithus. Haldeman, Supplement to No. I. of a Monograph of the Limniades, &c. 1S40. 
This name was first proposed by Professor Haldeman, as forming a sub-genus under 
Fucoides, and is now recognized by him as forming a distinct genus. 
Character. Stem free, simple, cylindric or subcylindric, vermiform or linear, never 
branched. 
1. 1. SCOLITHUS LINEARIS. 
Plate I. Fig. 1. a. b. c. 
Stem simple, rectilinear; surface nearly even, cylindric or compressed, sometimes 
apparently striated. 
Diameter to ^ an inch ; length from a few inches to several feet. 
This fossil, in its usual aspect, presents the appearance of numerous linear stems, often 
extending to one or two feet in length. Ordinarily it appears like a series of small pins or 
pegs driven into the rock in a somewhat regular manner, and at uniform distances. It 
preserves its distinctness even when the surrounding rock is much altered, as along the 
western face of the Green Mountains. In such situations, and often in others, the fossil is 
stained by oxide of iron, and the rock cleaves more easily in that direction. 
In the Second Annual Report of the Geology of Pennsylvania, Prof. Rogers speaks of 
this u marine plant ” as the best defined species discovered in this rock. He has also spoken 
of it under the name of Tuhulites ; but I believe no generic description ever appeared, 
previous to the one of Prof. Haldeman ; nor am I able to find in print the name tuhulites 
applied to this fossil, of anterior date. 
Fig. 1. a. A vertical or longitudinal view of a specimen of the rock containing these bodies. 
Fig. 1. b. A similar view of a specimen of partially altered and laminated sandstone from Pennsylvania, 
the tubes somewhat flattened. 
Fig. 1. c. Weathered surface of a specimen of the altered sandstone (crystalline or granular quartz), from 
Adams, Mass. 
