14 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 17, 



In these localities we do not as yet find the G. Sedgwickii, so abun- 

 dant in Peeblesshire and also in Tyrone ; other species take its place. 



Description of the Species. 

 Pleurotomaria Moorei, n. sp. Plate I. fig. 1. 



Turbinate, conical, transversely ribbed ; last whorl longer than the 

 spire of four or five whorls, which are somewhat flattened ; it has 

 three ribs above the band, and an angle a little below it, from thence 

 the base is smooth and flattened ; umbilicus none ? ; band a little 

 prominent, narrow, placed a little above the suture, which is hardly 

 channeled ; mouth rounded, and a little produced below ; shell rather 

 thick. 



This is presumed to be a Pleurotomaria, from general analogy and 

 the appearance of a band, but the lines of growth are not visible on 

 our specimen, which is much worn, and has part of the last whorl 

 broken away ; the shell when perfect must have been 2 inches long. 

 In general shape and proportion exceedingly like an undescribed Lud- 

 low species, but with the band narrower and not close to the suture, 

 and the ribs less numerous. 



Loc. Lower Silurian limestone, Stincher River, Ayrshire. 



Pleurotomaria latifasciata, Portlock? 



Syn. Scfdzostoma latifasciatum, Portl. Geol. Rep. PI. XXX. fig. 4. 



Our specimen is only a cast, and may be the same as Portlock' s 

 species ; the shape of the whorls is very similar. 

 Loc. Limestone of the Stincher River, Ayrshire. 



MuRCHisoNiA scALARis, u. sp. Plate I. fig. 2. 



Only internal casts, supposed to be the same as a common Bala 

 species ; the regular sharp angle in the middle of each whorl, and 

 the elongate shape enable us easily to recognise it. 



Loc. Limestone, Stincher River, Ayrshire. 



N.B. The exterior of perfect specimens shows the band of the 

 genus along the angle, and the fine striae curve back to it and return 

 again. Hall in the ^ Palaeontology of New York ' has figured many 

 species of this group of shells, and our shell may possibly be one of 

 them ; it can only be named provisionally. 



EuoMPHALUs? , reversed species. Plate I. fig. 3. 



Sections and fragments of this curious shell, badly preserved, are 

 not uncommon in the impure limestone. We have only the internal 

 cast ; the shell must have been thick, from the interval between the 

 much-depressed whorls, which are flattened above, abruptly rounded 

 or even squarish on the edge ; and the base, as far as we can see, is 

 again flat, so that the shell is nearly discoid. There are no traces of 

 septa, nor are the whorls really free. It has some resemblance to 

 Maclurea 7nagna, Hall, Palaeontology of New York. 



Loc. Greenish muddy limestone, Stincher River. 



