460 ME. S, S. BUCEMAN ON THE BAJOCIAN [Aug. 1895, 



stone as usually known ; but it is probable that in both cases the 

 Upper Freestone is represented by the upper beds of the series — it 

 is, in fact, a case of a marly condition of the Upper Freestone in 

 each locality. Though lithologically there is often no reason for 

 distinguishing between Oolite Marl and Upper Freestone, yet it 

 may be noted that palaeontologically five brachiopod-horizons can 

 be distinguished, and that these are independent of the lithology. 

 Thus there is the following sequence : — 



1. Bhynchonella cynomorpha, sp. n. 



2. Bhynchonella Tatei, Dav. 



3. Terebratula fimbria, Sow., at its acme, and Bhynchonella subobsoleta, 



Dav., rather below it. 



4. Terebratula curvifron.% Oppel, and T. submaxillata, Dav. 



5. Zeilleria Leckenbyi (Walker), at its acme. 



Of the above the two later horizons, Nos. 1, 2, may be taken to 

 indicate Upper Freestone or its equivalent, the three earlier Nos. 3, 

 4, 5, the true Oolite Marl. Table VIII. (p. 459) shows roughly the 

 sequential development of certain brachiopoda generalized. 



Summary and Conclusions. 



The following are the facts and conclusions advanced in this 

 paper: — 



1. A record of the stratigraphical sequence of the ' intervening 



beds ' between Stroud and Leckhampton. 



2. The correlation of the Gryphite- and Lower Trigonia-grits 



respectively. 



3. A demonstration of how the stratigraphical sequence has been 



affected by the ' Bajocian denudation.' 



4. The discovery of the importance of the Cold Comfort section, 



and the position of its beds. 



5. The discovery of a new ammonitiferous horizon in the Cottes- 



wolds. 



6. The bearing of this discovery on Jurassic chronology. 



7. Correlation of the ' intervening beds ' with Dorset strata, and 



the necessity of dividing the ' Witchellice hemera ' into this 

 and ' Sonninice hemera.' 



8. The geographical extent of the ' intervening beds ' ; and a de- 



monstration that the strata of the Witchellice hemera only 

 cover about 1| square miles in the Mid-Cottes wolds. 



9. Records of the chronological sequence of brachiopoda ; with 



special reference to their value in stratigraphical correlation. 



10. Description of certain new brachiopoda, particularly noticeable 



for their value as indicators of horizons. 



11. Notes on the development of certain brachiopoda, to show 



the importance to nomenclature of exactness in recording 

 horizons, and the importance to correlation of having a 

 nomenclature in accordance with development, by avoiding 

 a confusion of heterogenetic forms. 



