126 JOURNAL AND PROCEEDINGS. 
named Fucoides Verticales, in the series by Dr. James Hall.. They 
are not uncommon in the succeeding Clinton rocks, however. 
The paired Annelid burrows seem absent likewise. A cord- 
like Algze of the Grey-band is new to me, and is exceedingly rare. 
Only two specimens have been obtained ; both came from the same 
locality, and probably are merely fragments of one plant. They 
were not found in situ, but in a heap of rubbish where stone-cutters 
had been working. They present an appearance of smooth cylin- 
drical tubes of an equal thickness, lying on the surface of the flag. 
A closer examination reveals what I hold to bea fatal objection to 
their being referred to errant worm burrows—they dz/urcate and do 
not display the irregular thickness nor the curved shape of Nichol- 
son’s Planolites—(P. vudgares has about twice the diameter of this). 
The gentlemen of the Geological Section may remember that I ex- 
pressed an opinion that many of the vertical tubes named Scolithus, 
etc., as also the horizontal ones called casts of errant worms, may 
ultimately prove to be organic, or in other words, to speak more 
plainly in order to avoid misconception, plant remains. A con- 
clusion opposed to views very generally, but not universally accepted, 
requires explanation, and the evidence as yet in support of the asser- 
tion may not be deemed altogether satisfactory. 
The Scolithus of the Potsdam sandstone (Cambrian) I believe 
to bea true worm burrow. I noticed in a fragment many years ago 
the U-shaped base of a paired burrow, such as Professor James 
describes, both ends opening at the surface, as in the specimens from 
Madison, Wisconsin. No plant, I conceive, could ever have pre- 
sented a root-like process as here displayed. Arenicolites didy- 
mus, or A. Sparsus (Salter), paired tubes with circular openings, 
are frequently found in the Clinton rocks of Hamilton, and termin- 
ate in a like manner, habitations corresponding with those of the 
modern lob-worm. There are, however, vertical tubes filled in with 
a muddy sediment (slightly differing from the matrix in color), whose 
bases are unlike the ones above mentioned. They end ap- 
parently in a sharp conical root-like point. Lingula shells 
(single valves generally) are not uncommon in the beds here. 
In a paper by Sir Wm. Dawson I find the remark “that many of the 
filled-in tubes noticeable may have been produced by these 
Brachiopods.” Perhaps the same idea may have been entertained 
by Professor Shaler, recently, when he objected to the name 
