408 



sections of the Wolverhampton field having been afforded by Mr. J. 

 Barker. The principal points of novelty consist in drawing a clear 

 distinction betvpeen the upper or thicker measures, which contain the 

 10-yard coal, generally known as the Dudley coal, and the underlying 

 carbonaceous strata, or ironstone measures. The latter, rising from 

 beneath the J 0-yard coal, range to the N.N.E. from Wednesbury 

 and Bilston, in a long tract between the parallels of Walsall and Wol- 

 verhampton, extending to Cannock Chase. At the southern end of 

 the field, emerging from beneath the 10-yard coal, they occupy the 

 district between Stourbridge and Hales Owen, containing the well- 

 known " fire clayj" though some of the most valuable of the Wol- 

 verhampton iron-stones, beneath those called the " New Mine," are 

 here wanting, viz. the *' Gubbins," and " Blue Flats." This poverty 

 in the lower coal measures extends over all the district south of Dud- 

 ley. In the northern and southern ends of the district these lower 

 measures represent the whole carboniferous system ; and in various 

 natural sections near the Hagley and Clent hills, the author has de- 

 tected them, in very feeble bands, passing upwards and conformably 

 into the lower new red sandstone. Besides the open works formerly 

 alluded to by him in previous memoirs, Mr. M. now states, that his for- 

 mer conjectures respecting the passage of the lO-yard coal beneath the 

 new red sandstone which flanks it on the east and west have been ve- 

 rified by the efforts of the Earl of Dartmouth, who, after sinking to a 

 depth of 15 1 yards through strata of the lower new red sandstone, has 

 very recently succeeded by further borings, carried down to the depth 

 of 290 yards, in discovering the 1-foot, 2-foot, and "Brooch" coal 

 seams, which overlie the 10-yard coal throughout the Dudley field. 

 These operations have taken place at Christchurch, one mile beyond 

 the superficial boundary of the coal-field. 



Besides the plants so common in all carboniferous tracts, the author 

 has observed the presence of animal organic remains. Unios of several 

 species are abundant j and in the northern or lower part of the field 

 he has extracted fragments of fishes, which have been named by Pro- 

 fessor Agassiz, 



Megalichlhys Hibbertii, 



M. Sauroides, 



Diptodus gibbus ; 



together with scales, coprolites, &c., proving an identity between the 

 animals deposited in these coal measures and those of Edinburgh, de- 

 scribed by Dr. Hibbert. The same species, it will be recollected, have 

 been pointed out by Sir Philip Egerton as occurring in the N. Staftbrd- 

 shire coal-field, and one of them has been observed by Mr. Prestwich 

 in the coal-field of Coalbrook Dale. Mr. Murchison, however, re- 

 marks that he has not yet observed any marine remains in these coal 

 measures similar to those of Coalbrook Dale ; and nothing yet found 

 can invalidate the inference that the coal of Dudley and Wolverhamp- 

 ton may have been accumulated exclusively in fresh water. 



b. Siiurian rocks. — The mountain or carboniferous limestone and 

 the old red sandstone, which in so many other parts of England form 

 the support of coal tracts, being wanting, this field reposes directly 



