OEGANISMS IN ACADIA. 157 



this part of tho sli(_'l], but of the larger eud quite a number. Some of these slightly exceed 

 the dimcusiou.s of the Russian specimens. They show traces of the cross-striation men- 

 tioned by Dr. Schmidt, but no satisfactory evidence of a siphon was obtained. 



Size. — Length of the part of the shell preserved, 5| mm. Width at large end, 8 mm. ; 

 at small end, IJ mm. 



Horizon and Locality. — Collected from Band b of Div. 2 of the Basal series at Hanford 

 Brook ; and for the Geological Survey of Canada, in calcareous grey sandy shale in the 

 upper part of Band b of Div. 1 of the St. John group at Belyea's Landing, Westheld, N.B. 

 Scarce. Occurring in clusters, buried at all angles in the mud. 



VII.— ANHfEI.IDA. 



Under this class may proA'isionally be placed certain tracks which are very character- 

 istic of the lower part of the Cambrian system in this part of Canada. 



These appear to be essentially the same as those described by Prof. O. Torrell from 

 the rocks of the Sparagmite Stage (=Fucoidal and Eophytou sandstone) of the Cambrian 

 rocks of Sweden, under the name of Areniœliles gigas. Torrell found that Mr. Salter had 

 used Arenicolites for markings of a different kind, and says also that Salter's name Ilel- 

 minthiles does not apply to these tracks. He therefore proposed the name 



PSAMMICHNITES, [Torrell, 18t0?] 



To include these peculiar trails of a large size found at this horizon of the Cambrian. 

 This word is intended to apply to " such vermiform, llexuous, linear tracks as are made 

 either by worms, by crustaceans or b}^ molluscs." 



PSAMMICHNITES GIGAS, Torrell. (PI. XI, figs. 1«-^.) 



Torrell's description oî Arenicolites gigas is as follows' : — 



Elevated, arched-flexuous, linear, convex bodies, with obscure transverse lines and 

 ridges, obscurely sculptured, marked by a narrow median nerve, imitating remarkably 

 the vermiform excrements of the lob-worm, met with on shores. Length of the largest 

 fragment, 187 cm. ; width, 24 cm. Found in a boulder of sandstone from the Lower 

 Cambrian near Cimbrishamn in Scania. 



Dr. Torrell says that the fossil was found in a large block of the same kind of rock 

 as the Cimbrishamn sandstone, and there can be scarcely any doubt that it is in situ iu the 

 neighborhood. He also remarks that these fossils cannot be algre, and that this great 

 winding figure can hardly spring from anything else than a worm. He says that the 

 objection made that they are much greater [tracks] than [are made by] any living 

 animals of the same type, loses its force since Geinitz described a Silurian worm [Phyl- 

 lodociles Thuringiacus) which in size at least approaches this. Torrell regards it as much 



' Lunds Univ. Arsskrift. torn, vi, p- 34, 1869. Lund, Sweden. 



