JURASSIC AND TRIASSIC BRACHIOPODA. 189 



still to be a very rare fossil in Great Britain, but it occurs rather abundantly in the 

 Inferior Oolite of Conde-sur-Sarthe, near Alencon, in France. 



175. Rhynchonella furcillata, Theodori. Dav., Ool. Mon., p. 69, PI. XIV, figs. 



2—5 j Sup., PI. XXVII, figs. 1—3. 



Nothing new. This species occurs throughout the Middle and Upper Lias. It was 

 found by Mr. R. Tate in the Am. armatus beds of Hallaig, Raasay, in Scotland, also in 

 the Zone of Am. Jamesoni at HuntclifF, and in the A. armatus beds at Kirby Underdale, 

 in Yorkshire. Some very remarkable transverse specimens from the Middle Lias or 

 Marlstone, near Shipton Grove, may be seen in the Museum of the School of Mines, 

 London. 



176. Rhynchonella rimosa, Von Buck. Dav., Ool. Mon., p. 70, PI. XIV, figs. 6, 6 a ; 



Sup., PI. XXVII, fig. 10. 



Nothing new. Bh. rimosa occurs in the Zones of Am. Jamesoni, A. capricornus, 

 and A. margaritatus (Middle Lias). Mr. R. Tate quotes it from the Zone of Am. 

 Jamesoni at HuntclifF and Coatham Scars, in Yorkshire. It is especially abundant in the 

 Am. Ibex Zone at Churchdown Hill, Gloucestershire (P. Smithe). It has also been 

 found at Tobermory in the Island of Mull, Scotland. Up to a certain age the ribs are 

 all simple, and the fold scarcely raised above the general convexity of the valve, but with 

 age these ribs combine by twos or threes near the margin, forming larger ribs in adult 

 individuals. Bh. rimosa rarely exceeds 9 lines in length, by something less in breadth. 

 Professor Brauns considers Bh. rimosa curviceps, Quenstedt, and T. sub-serrata, Miinster, 

 to be synonyms of Bh. rimosa. 



177. Rhynchonella serrata, Sow. Dav., Ool. Mon., p. 85, PI. XVI, figs. 1, 2. 



This fine and very distinct species occurs in the upper portion of the Middle Lias or 

 Zones of Am. margaritatus and Am. spinatus. It has been obtained by Mr. J. F. 

 Walker from Sowerby's original locality Chideock, near Charmouth, Lyme Regis. 



contrast to the beds already described ; for, although only thirty-eight feet thick at Leckhampton Hill, or 

 one sixth of the whole formation, yet it preserves a very uniform thickness over nearly the whole district, 

 and at its south-east extremity is the sole representative of the Inferior Oolite, and contains many species 

 of Brachiopoda. Towards the south-eastern part of the district the Ragstone gives place to a coarse rubbly 

 white Oolite called Clypeus-grit. Over this deposit comes the Fuller's Earth, separating the Great from 

 the Inferior Oolite, and containing a general assemblage of forms common to both. 



