Mr. J. W. Salter on Cambrian Fossils. 2H 



with the idea at least of large serpents. But according to actual 

 knowledge, and the positive records of zoology, the serpent between 

 10 and 12 feet in length from the tertiary strata of Salonica must 

 be deemed an extinct species." For this fossil Professor Owen pro- 

 posed the name of Laophis crotaldides. 



3. " On some additional Cambrian Fossils from the Longmynd." 

 By J. W. Salter, Esq., F.G.S. 



In March 1856 Mr. Salter communicated the discovery of traces 

 of Annelides and probable fragments of a Trilobite, accompanied by 

 ripple-marks, in the sandstone-beds of the eastern part of the Long- 

 mynd. During the last summer he collected many more materials 

 for the elucidation of the palaeontology of the Longmynd rocks ; and 

 in the present paper described the occurrence of abundant Annelide 

 markings, referable to two species (one of them new), throughout 

 a mile of thickness in the lower portion of the nearly vertical shales, 

 sandstones, and flagstones of the Longmynd, from Church Stretton 

 to the Portway. 



Wave- or surf-marks, ripples, sun-cracks, and rain-prints were 

 also described ?.s occurring at several localities on the surfaces of 

 these laminated rocks of the Longmynd. 



Arenicolites sparsus was proposed as the name for the new species 

 of double worm-hole above alluded to. Mr. Salter also adverted to 

 the discovery of numerous vertical worm-tubes in the quartz rock of 

 the Stiper Stones. These he believes to be the same as the Scolithus 

 linearis of Hall, found in the Potsdam sandstone of North America. 



He proposes the term Arenicolites for all fossil worm-holes with 

 double openings, and Helminthiies for the superficial trails. 



4. " On some Species of Acidaspis from the Lower Silurian beds 

 of the South of Scotland." By Professor Wyville Thomson. Com- 

 municated by J. VV. Salter, Esq., F.G.S. 



The author described three new species of the trilobitic genus 

 Acidaspis, from the Lower Silurian flagstones with Graptolites and 

 Orthoceratites of Pinwhapple Glen, and one from the overlying 

 sandstone of Mullock Hill, Ayrshire. The names proposed for these 

 species were Acidaspis Lalage ; A. hystrix ; A. unica ; and the fourth, 

 A. callipareos. 



5. " On two Silurian Species of Acidaspis from Shropshire." By 

 J. W. Salter, Esq., F.G.S. 



In this communication Mr. Salter gave descriptions and figures 

 of Acidaspis coronata, sp. nov., from the Lower Ludlow Rock, and 

 A. Caractaci, fron the Caradoc or Bala Sandstone of Gretton. The 

 latter species had been previously described, but r»ot figured. 



January 21, 185 7.— Colonel Portlock, R.E., President, in the Chair. 



The following communications were read : — 



1. "On some Fossiliferous Ironstone occurring on the North 

 Downs." By Joseph Prestwich, Esq., F.ll.S., F.G.S. 



Besides a drift of red loam with flints, and the few local outliers 

 of lower tertiary sands and pebble-beds, there are scattered on 



