Page:Quarterly Journal of the Geological Society of London, vol. 34.djvu/49

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R. ETHERIDGE, JUN., ON LOWER-CARBONIFEROUS INVERTEBRATA.
25

E. BTHERIDGE, JUN., ON LOWER-CARBONIFEROUS INVERTEBRATA. 25 At Drumsheugh, Dean Bridge, certain beds of sandstone and shale have been investigated by Mr. Henderson and Mr. Gall ; and the fossil contents go far, I think, to prove Mr. Henderson's view of the identity of this bed with the Woodhall Shale, as amongst them are two of the most characteristic shells of the latter bed, Schizodus Salteri and Pandora ? typica. Another species accompany- ing them, but not found at Woodhall, is Anthracoptera't obesa, mini, which also occurs at Craigieith Quarry, and has been obtained by Mr. Henderson, and also by Mr. Bennie, in an altered shale under- lying trap at the north end of Corstorphine Hill, near Edinburgh. A shell which afterwards becomes exceedingly characteristic of the Burdiehouse beds makes its first appearance in black shale in the Water of Leith at Kate's Mill near Slateford. I have elsewhere de- scribed this species as Anthracomya scotica, and shown that it may be identical with Unio nuciformis, Hibbert ; but as I cannot trace the type of the latter, it is a question which will, I am afraid, re- main unsettled. Mr. Henderson has only obtained fragments from Kate's Mill ; but even these are infested with the little Spirorbis carbonarius, as are nearly all the individuals from the horizon of the Burdiehouse Limestone. The most interesting point in connexion with the Entomostraca of the Wardie Shales is the first appearance of the Coal-measure genus Leaia, for the discovery of which we are indebted to Mr. C. W. Peach, in an ironstone nodule at Wardie. Little has been written on the Invertebrates of the Burdiehouse Limestone and associated beds. They appear to be chiefly remark- able for the abundance of Spirorbis carbonarius and its varieties, the Anthracomya previously indicated, and the great quantity of Ostracoda forming what is usually termed " Cyprid Shale." The more important forms are Leperditia scoto-burdigalensis, Hibbert, L. OJceni, Miinster, and Daphnoidea (or Cypridina) Hibberti, Jones. It is hardly necessary to point out, as the previous Table suffici- ently indicates it, the close correspondence which exists between the organic remains from the bands of marine shale found at Woodhall, Drumsheugh, Craigieith, Craiglockhart, and Granton. Conclusion. In the foregoing pages I have endeavoured to give, first, an out- line of our knowledge of the Invertebrate fauna of the Calciferous Sandstone Series up to the present time ; secondly, I have given de- scriptions and figures of numerous species from Mr. Henderson's col- lection, thereby increasing the fauna largely ; thirdly, I have appended some remarks on the first appearance of many of these fossils, and indicated the occurrence of, at least, three or four marine beds in the Calciferous Sandstone Series, in addition to that mentioned by Mr. Salter at Clubbidean. They are: — Craiglockhart Quarry with Discina nitida, Lingula squamiformis ?, L. mytiloides, &c. ; Woodhall, Water of Leith, with a copious fauna (see Table) ; and (if not iden- tical with the latter) Drumsheugh ; whilst the fourth may perhaps be indicated by the occurrence of Lingula squamiformis at Dean Bridge, Water of Leith.