160 



Following these beds in an ascending order, tlie marnes et 

 calcaire marneux a Am. hisulcatus are clearly the true equivalent 

 of the " zone of Ammonites Buchlandi," of which. Am. lisulcatiis, 

 Brng.,=^m. multicostata, Sow., is the dominant species in France, 

 and the form that appears to prevail in the Cote-d'Or. I saw 

 several specimens of this species, which were identical with our 

 own, from the same zone in Gloucestershire, Warwickshire, 

 and Dorsetshire. The bed with Am. Sciinoniamis, d'Orb., likewise 

 occurs in the vale of Gloucester, as I have a beautiful example 

 of this Ammonite obtained near Bredon, from the deep cutting 

 made in the formation of the Midland Railway. 



The bed with Am. rotiformis, Sow., was exposed in excavating 

 the Lower Lias Shales at Cold Pool, in the construction of the 

 Cheltenham and Gloucester Railway; it is found hkewise at 

 Saltford, near Bristol, and at Lyme Regis, Dorsetshire. The 

 bed with Am. stellaris, Sow., and Am. Birchii, Sow., occupies a 

 higher position, and forms a portion of the zone of Ammonites 

 ohtusus, Sow. ; most of the specimens of Am. stellaris, Sow., in 

 M. Martin's collection are, in fact, true examples of Am. 

 ohtusus, Sow., and from the same localities were obtained Am. 

 Sauzeanus, d'Orb., and Am. Dudressieri, d'Orb. Am. Oxynotus, 

 Quenst., is grouped with these species, but in Gloucestershire 

 this Ammonite occupies a higher position and characterizes a 

 considerable zone, consisting of beds of dark clay, largely 

 charged with the peroxide of iron; from these, many years 

 ago, I collected a very large number of type specimens 

 identical with the German forms. Swindon, near Cheltenham, 

 and the excavations for the New Docks, Gloucester, may be 

 mentioned as localities from whence they were largely obtained. 



III. — "LiAssiEN OTJ Lias Moten" 



Consists of the following sub-divisions : — 

 a Marnes et calcaire marneux a Ostrea gigantea. 

 h Marnes feuilletees et micacees. 

 c Mames et calcaires argileuse bleuatres a Am. Davcei et Am. Bechei. 



This division, or the Lias Moyen, attains a considerable 

 development at Semur (Cote-d'Or). The under beds consist of 



