88 



UPPER COAL-MEASURES NEAR MANCHESTER. 



strata consist entirely of argillaceous marls or sandstone. This indeed is quite what the geologist 

 would expect to find amid strata composed of such rapid alternations of marl, sandstone, grit, shale, 

 and limestone. Professor Phillips also alludes to the occurrence of reddish masses of silex in the 

 limestone, of which he says, " These will doubtless recall to your recollection several freshwater 

 limestones on the Continent." He then proceeds to give the following explanation of the nature of 

 the organic remains : 



"The organic remains of this series are terrestrial, fiuviatile, and of doubtful origin. The plants 

 are all terrestrial, namely, 



" Aster 'ophyllites, one species; Calamites, two or three species (C, nodosus, according to Wil- 

 liamson) ; Cyclopteris, one species ; Lepidodendron, one species [L. Sternbergii according to 

 Williamson); JVeuropteris cordata (Lindley and Hutton, Fossil Flora; same species at Le Botwood) ; 

 Pecopteris, three species ; Stigmaria Jicoides. Leaf of a monocotyledonous plant, similar to one 

 occurring at Le Botwood, Salop, with portions of other very narrow monocotyledonous leaves re- 

 sembling Noggerathia foliosa, some of which are brown, transparent, and elastic. These plants 

 occur in the shale, bass, &c, alternating with the limestones 1 . 



" Shells. The most characteristic is a microscopic spiral shell of few volutions, which touch one 

 another like Planorbis when young, but when old are extended into a free tube like Vermetus or 

 rather like Vermilia. The shell is sinistral like Planorbis, but sometimes shows proof of being 

 attached on one side like Spirorbis. Lines of growth, strong, somewhat irregular, deficient in 

 parallelism, and oblique to the axis of the tube (D. 10.) as in Planorbis; faint spiral striae, can 

 just be seen. This shell, which I have identified with your Salopian planorboid shell, is also pro- 

 bably the same as a species I have seen from the coal measures of Fitzgerald's Colliery near Man- 

 chester, as well as from the lower part of the Yorkshire and Newcastle coal-fields." (See wood-cut, 

 p. 84. The figures D. 1. to 10. represent this shell Microconchus carbonarius .) 



" The only other distinct shell which I have obtained from the limestone looks so very like a 

 young Modiola that I hesitate to call it Unio. (Wood-cut, p. 84. fig. c.) It is a tumid little shell, 

 smooth, but with very distinct lines of growth, prominent beaks, and rather short straight hinge 

 lines. In the argillaceous beds associated with the limestones are three species of Unio. The most- 

 common of these is nearly elliptical; the hinge line deviates considerably from parallelism to the front, 

 and ends in a prominent angle; lines of growth strong, shell very thin, beaks slightly prominent. 

 Mr. Williamson has inaccurately referred this shell to Unio nuciformis. It occurs in the red beds 

 above the limestones, in the black bass, and in the underlying coal measures. 



" The second species, which I named U. linguiformis ( U. Phillipsii of Williamson), is transversely 

 elongated, three times as wide as long ; the hinge line deviates very little from parallelism to the 

 front lines of growth ; shell fine, very thin and smooth. This shell is found in the black bass. 

 The third species, which I named Unio rugulosus, is of obliquely expanded or semi-elliptical 

 form, the hinge line forming the diameter. Surface concentrically marked with broken undulations, 

 often showing radiations on the posterior slopes; shell exceedingly thin. Uniomdce of the same 



1 Mr. Williamson, in the interesting memoir before alluded to, states the important fact, that in the red shale, 

 sixty feet above the main limestone, and therefore in the beds of transition between the Lower New Red and 

 the coal measures, Mr. Mellor and himself discovered many impressions of plants, among which were Calamites 

 decoratus, C, nodosus, Lepidodendron Sternbergii, Neurojjteris cordata, Stigmaria ficoides, &c. These plants 

 occur as nearly as possible in the position of the beds overlying the upper coal seam of the Shrewsbury field. 



