COTTESWOLD DISTRICT. 61 



Lower Beds of the Inferior Oolite. 1 A list of those determined is given at p. 270. 

 It was likewise, I believe, the opinion of Prof. R. Tate that several undescribed 

 species of Gasteropods (minute) were to be found in this series. Hitherto I confess 

 that my own researches have not been very successful. Moreover, if Mr. 

 Witchell's specimens are to be taken as a sample, there are not many people who 

 would venture to describe them. Whilst on the subject of these Micromorphs I 

 may observe that the Pea-grit of Leckhampton, Crickley, &c, contains several 

 small Gasteropods, many of which appear to be merely the young of well-known 

 species. As such extremely small shells would require different artistic treatment 

 from the bulk of the Gasteropoda to be described in this memoir, it might be con- 

 venient to place them in a separate category by way of supplement ; that is to say, 

 if they should prove to be of sufficient importance. 



The Pea-grit is exposed on the flank of the hill, and on this horizon the earliest 2 

 Nerinaeas in the Cotteswolds may be noticed. The same bed is well shown in a 

 roadside cutting near Longford's mill, and has there afforded several species of 

 Nerincea usually distinct from those of the Oolite Marl. High up in the freestone 

 series is another bed with Nerincea, which may probably represent the extremely 

 rich beds in connection with the Oolite Marl on the other side of Stroud. The 

 third Nerinsean horizon is that in the Glypeus-grit, which we have now traced con- 

 tinuously through so many exposures. 



The Glypeus-grit is characterised by Nerincea Guisei, Witc. 

 The Freestones, Oolite Marl, &c, by Nerincea Gotteswoldice, Lye. 



— gracilis, Lye. 

 The Pea-grit by Nerincea producta, Witc. 

 — pisolitica, Witc. 



These three NerinEean horizons, in the Pea-grit, the Oolite Marl, and the Glypeus- 

 grit, respectively, have also yielded the bulk of the somewhat scanty collections of 

 Gasteropoda which have been obtained from the more classical districts of the 

 Cotteswolds. On the other hand, the Upper Trigonia-grit and the Gryphite-grit, 

 well stored as they are with other fossils, seem to be deficient in this respect. 

 Hence the Ragstones, though far more fossiliferous as a whole than the beds of 

 the Murchisonce-zone in this neighbourhood, contain fewer Gasteropoda. 



Rodboeough Common, about three miles north of Nailsworth Hill. This again 

 is classic ground, many both of Dr. Lycett's and Mr. Witchell's specimens coming 

 from here. I subjoin a profile, showing the upper or Ragstone-beds in some detail. 



The Upper White Oolite is the bed we have generally met with hitherto in the 

 Cotteswold Hills, usually forming the top of the Inferior Oolite. The next three 



1 ' Quart. Journ. G-eol. Soc.,' vol. xlii (1886), p. 264, et seq. 



2 The Lower Limestone has hitherto yielded only imperfect fragments of Nerincea. 



