198 J. Starkie Gardner — On the Gault Aporrhdidce, 



series. Probably, in otber sections in various parts of the Coal-field, 

 some of these higher Coal-measures may be traced, suggesting that a 

 much greater thickness of Upper Coal-measures than we at present 

 know of spread over the whole extent of the Coal-field previous to 

 its elevation and denudation. 



Stimulated by the Sandwell success, other companies are forming 

 to search for Coal under the red rocks of large estates situate still 

 further away from the " eastern boundary " of the old Coal-field 

 than Sandwell. Is it not probable that still higher Coal-measures 

 may be recognized ■? Is it not possible that the Spirorbis Limestone 

 may yet be found over all, to prove the relation between the South 

 Staffordshire and the Warwickshire Coal-fields on the one hand, and 

 the Wyre Forest Coal-field on the other ? 



II. — On the Gault Aporrsa'i'd^. 

 By J. Starkie Gardner, F.G.S. 

 (PLATE VI.). 

 (Continued from page 130.) 

 Group 4. — Spire moderately long, generally without carinas, 

 always ribbed transversely. Wing expanded and quadrate, pro- 

 longed posteriorly into a sharp point. 



Type : — A. jParTcinsoni. 



Aporrhais marginata, Sowerby. PI. VI. Figs. 1, 2, 3. 



Synonym, : A. Orbignyana, Pictet, and Eoux. 



Description. — Shell elongated, the spire forming an angle of 33° 

 and measuring "046 : composed of eight convex angulated whorls, 

 which are closely covered with spiral striae, each alternate one being 

 nearly twice as prominent as the intervening one. The whorls are 

 ornamented by short elongated ribs, which are nodose and tuber- 

 cular on the lower, but thin and linear on the upper whorls, 

 and more numerous and very fine towards the apex. These ribs 

 have an occasional tendency to form varices. On the body- 

 whorl there are two more or less distinct rows of tubercular nodes ; 

 the uppermost row, being the more important, is continued in the 

 form of a, tuberculated ridge on the wing process. The wing is large, 

 broad and quadrate, and thickened in the same manner as in the 

 recent A. pes-pelicani, which our shell much resembles. It is sinuous 

 at its margin, and terminates anteriorly in a blunt process ; posteriorly 

 ending in a long and rather recurved sabre-shaped spike, deeply 

 grooved ventrally. Between this and the margin of the remainder 

 of the wing is a sinus. The mouth is narrow, and shaped, as in 

 A. pes-pelicani, like a lance-head point downwards. The anterior 

 canal is moderately long, - 021, delicate and straight. The inner lip 

 and underside of the pterygoid process are enamelled ; length of the 

 wing to the end of spike is "032. Fig. 3 represents a variety from 

 an upper bed in which the ribs continue thin and linear to the last 

 whorl, instead of being nodose or tubercular. 



Distribution. — Found most abundantly at Folkestone, where it 



