368 G. J. HINDE ON ANNELID JAWS FEOH THE WENLOCK AND 



28. On Annelid Jaws from the Wenlocz and Ludlow Formations 

 of the West of England. By Geoege Jennings Hinde, Esq., 

 E.G.S. (Eead May 12, 1880.) 



[Plate XIV.] 



In the paper which I had the honour to bring before the Society in 

 the early part of last year, on Annelid jaws from the Palaeozoic 

 rocks of Canada and Scotland*, I ventured to express an opinion that 

 these small bodies would be very likely found in rocks of similar age 

 in this country. Since that time I have had the opportunity of 

 searching various exposures of the Silurian rocks at Dudley, Much 

 "Wenlock, and Iron Bridge, in Shropshire, all well-known localities 

 for Wenlock fossils ; and in each place I have discovered Annelid 

 jaws more or less abundantly. In quarries at Stoke-Edith, and near 

 Ludlow, the rocks of Upper Ludlow age also yielded these remains, 

 though by no means so abundantly or in such a good state of 

 preservation as the Wenlock rocks — a result perhaps rather owing 

 to the less favourable character of the matrix for their preservation 

 and to the more limited exposures of the rock-surfaces than to any 

 deficiency in the number of the Annelids. Altogether, from the 

 above-mentioned localities my search produced between two and 

 three hundred specimens of these minute remains : but the greater 

 number of these proved on examination to be only fragmentary 

 specimens ; many perish in the process of cleaning them away from 

 the matrix ; and thus only about one fourth of the total number are 

 available for description. It is a matter of surprise that these 

 fossils, occurring thus numerously in a district renowned as a clas- 

 -sical hunting-ground for Silurian fossils, should hitherto have 

 escaped the notice of geologists ; but their very small dimensions 

 (the largest specimen met with not exceeding one fifth of an inch 

 in length) will sufficiently explain the cause of their long con- 

 cealment. 



The character of the rocks containing these jaws is closely similar 

 to that in which they abound in Canada. In the Wenlock district 

 they appear in the bluish-grey calcareous shales or mudstones 

 which form strata of greater or less thickness between the beds of 

 limestone ; and in quarrying this rock these intervening shales are 

 usually piled up on one side in large mounds of debris. It is only 

 on the surfaces of shale recently exposed that these fossils are 

 visible; nor are they by any means uniformly dispersed in it; for whilst 

 in one part of a quarry fragments can be noticed on every slab of 

 rock, in another part of the same quarry similar shale proves desti- 

 tute of all traces of them. The Upper Ludlow rocks, as shown in 

 quarries at Stoke-Edith and on the banks of the river Terne at Lud- 

 low, are more arenaceous and of a much harder character than 

 those of Wenlock age ; and consequently these fragile remains have 

 * Quart. Journ. Geol. See. vol. xxxv. p. 370. 



