38 proceedings of the geological society. ^jun© 11^ 



June 11, 184.5. 



E. Solly, Esq., F.R.S., F.L.S. ; Alexander Keith Johnstou, Esq. ; 

 the Earl of Lincoln, and B. CunlifFe, Esq., were elected Fellows of 

 the Society. 



The following communications were read : — 



ilceozoic Bocks ofth£ Isle of Man, 

 Gumming, M.A. 



[This paper is postponed for the present.] 



1. On the Pal(Bozoic Rocks of the Isle of Man. By the Rev. J. G. 

 Gumming, M.A. 



2. Description o/* Footmarks and other Imprints on a slab of}^EW 

 Red Sandstone, from Turner's Falls, Massachusetts, 

 U.S., collected by Dr. James Deane of Greenfield, U.S. By 

 Gideon Algernon Mantell, Esq., LL.D., F.R.S., F.L.S, 



Having recently received from Dr. James Deane a small slab of 

 stone covered with Ornithichnites belonging to two species, and some 

 of these imprints exhibiting the character of the surface of the der- 

 mal integument more distinctly than any other specimen brought to 

 this country, I am desirous of submitting it to the examination of 

 the Society, with the following description which accompanied it. 



The slab is about two feet in diameter and half an inch in thick- 

 ness. On the upper surface there are two rows of small elegant 

 footmarks, of the species termed by Professor Hitchcock Ornithich- 

 nites gracillima ; one row consists of five, and the other of six con- 

 secutive impressions. There is also a row of four footprints of a 

 much larger species, the O. fulicoides (so named from their re- 

 semblance to the footmarks of the recent cinereous coot, Fulica 

 Americana), These are arranged around the circumference of the 

 slab, and their alternate order proves that they have been impressed 

 by the same individual. " There is a rare peculiarity displayed in 

 these larger impressions that adds greatly to their interest : it is the 

 markings of the papillae, and folds of the cutaneous integument, 

 which are very distinct ; and this character," says Dr. Deane, " I 

 have only observed in two other examples. The papillae may be 

 seen most distinct in the first, second, and fourth footstep ; particu- 

 larly ill the last of the series, on the top of the slab." The three 

 rows of footprints above-described embrace fifteen impressions, and 

 exhibit the articulations of the toes perfectly. The surface of the 

 stone is pitted by rain-drops, from a shower which must have fallen 

 before the birds walked over the soft mud and made the footprints. 

 There are also indistinct traces of the trails of worms, and of an 

 Annelide. 



On the reverse of the slab there are the casts of four consecutive 

 impressions of Ornithichnites gracillima ; and a row of two, of di- 

 mensions intermediate between those of the preceding varieties. 



II 



