J. F. JAMES — THE GENUS SCOLITHUS. 



Figure 5 — Scolithus clintonensis (n. sp.)= 

 Fucoides verticalis, Hall. (After Hall.) 



ring in the Potsdam sandstone of Canada,* referred to the species as marking the 

 sandstone abundantly over considerable spaces, saying that it consists, "where the 

 rock is weathered, of straight vertical cylindrical holes, of about an eighth of an 

 inch in diameter, descending several inches, 

 and where the rock is unweathered of corres- 

 ponding solid cylinders, composed, apparently, 

 of grains of sand cemented by a slightly calca- 

 reous matrix, more or less tinged with peroxide 

 of iron. Mr. Hall and other American geolo- 

 gists include them among the fucoids of the 

 rock, but they appear to me more like worm- 

 holes. In one or two instances I have perceived 

 that the tubes are interrupted in their upward 

 course by a thin layer of sand, a portion of 

 which descends into them and stops them up; 

 and from this it would appear that the cylin- 

 ders were hollow when the superincumbent 

 sand was spread over them. Whatever may 

 be the origin of the tubes, they strongly mark 

 many beds in the upper portion of the sand- 

 stone throughout the Canadian portions of its 

 distribution." This opinion has been accepted 

 by most authors who have written upon the 

 genus, although some still adhere to the idea 

 that the fossils are of vegetable origin. 



In 1857 Mr. J. W. Salter noted f finding in the Stiper stones of Shropshire, Eng- 

 land, vertical tubes similar to Scolithus linearis. He proposed to use the term 

 Scolithus or Scolites for single tubes or burrows, either vertical or horizontal, but the 

 suggestion does not seem to have been accepted. 



In 1858 was published the Geology of Pennsylvania, by Henry D. Rogers. In 

 the course of this report J Scolithus linearis is alluded to in one place as a plant, and 

 in another as an annelid burrow. In discussing facts relative to the deposition of 

 the primal white sandstone he says it must have been deposited in quiet waters, 

 because of the "universally perpendicular position of its long slender delicate stem- 

 like fossil, the Scolithus linearis, winch seems to have been enclosed by the settling 

 sand with as little horizontal bending motion of the stalks from any current as 

 when a Held of standing corn is enclosed and bedded up in gently-falling snow." 



Again, when referring to the fossils of the Primal strata, he says the species was 

 alluded to in the reports of the Pennsylvania and Virginia surveys under the name 

 of Tninilii, s.|| He describes it as usually smooth, but sometimes waved or grooved 

 transversely to the axis ; always perpendicular, " suggesting the idea of perforations 

 by some marine worm. < hie end of the fossil always terminates at the upper sur- 

 face of the bed of sandstone enclosing it, and usually in a rudely flattened knob or 

 bead, giving to the whole a likeness to a large, long pin. This knob is probably a 

 casl formed in a wide conical funnel-shaped month of a cylindrical perforation." 

 This form is abundant in the Blue ridge of Virginia and at Chickiea on the Susque- 

 hanna in Pennsylvania. Similar forms occur in higher formations. The figure 



♦ Quart. Jour. Gteol. 8oc. London, rol. viii, 1852, pp. 199-213. 

 ; Quart, .lour. Geol. 8oc. London, rol. xiii, 1857, p. 204. 

 i Volume -', pp. 780, 816 • 16 

 I have i n unable t" find any use of this nam ■ in the reports mentioned. 



