Ammonites opalinus 

 * dispansus 



Aalensis 



discoides 



serrodens 



Comensis 



Hircinus 



Leckenbyi . . 



Boulbiensis . . 



Jurensis 

 • radians . . . . 



insignis (2 varieties) 



striatulus 



variabilis 

 - fimbriatus . . 



Upper Lias. 



Sands. 



Lower. Middle. Upper 



Inferior Oolite. 



Ilminsterensis 

 complanatua 



The Sands have been divided into three portions as they contain three 

 fossUiferous horizons at several localities in the Cottes wolds. The two 

 species which are stated to pass upwards into the Inferior Oolite are given 

 upon the authority of Professor Quenstedt and of Dr. Oppel, the former of 

 whom has figured them (Jura, pi. 42 and 45) from the Brown Jura 'a! of 

 Wurtemburg, in England they have not been found higher than the Sands. 



It will be perceived from the foregoing table that of the thirteen 

 Ammonites found in the upper portion of the Sands at Frocester Hill, and 

 other localities, eight do not pass downwards to the Lias, nor lower than 

 the highest bed of the Sands; that the other five occur throughout the Sands, 

 and also in the upper Lias ; and that the remaining five species of the 

 lower Sands are also Liassic, but do not pass upwards into the Sands higher 

 than the lowest fossiliferous- band near to their base. All the Ammonites 

 of the lowest zone in the Sands are therefore Liassic, but one of them 

 {A. variahilis) is a boundary species, and passes downwards into the Upper 

 Lias only a few inches, as wiU be found in the sands on the coast of 

 Yorkshire, at Ilminster, at Nailsworth in the Cotteswolds, and in France. 

 Of the Ammonites in the Upper Sands two are also boundary species, they 

 have been found rarely very near to the upper boundary of the Sands at 

 Frocester HiU, one of them (A. opalinus) has also occurred in the same 

 position at Burton Bradstock, Somerset, and at Blue "Wick on the 

 Yorkshire coast. In "Wurtemburg, on the other hand, both species occur 



* These species occur abundantly in the Cotteswolds. 



