and the keel very promineut. The typical form of A. inaignis in both 

 its aspects occurs rarely in the Upper Sands at Frocester Hill, the lower 

 zone at Nailsworth has also supplied young specimens, but I have failed to 

 ascertain that it has ever been procured in the Upper Lias.* The flattened 

 variety ffahalis) has been obtained in the Upper Sands at Chalford and in 

 the Upper Lias of Robin Hood's Bay, Quenstedt has figured it from the 

 horizon of the Sands in Swabia. 



Ammonites striatulus, Sow., syn. A. Thouarsensis, d'Orb., A, Comensia 

 d'Orb , A, radians depressus, Quenstedt, A. Thotiarsetisis, Dewalque, some 

 specimens with more closely arranged ribs approximate to A. radians, with 

 which it has been arranged by some authors, but it never attains the 

 dimensions of that species, and there appear to exist sufficient distinctions 

 between them in the characters of the septa ; it is common in the 

 Upper Sands at Frocester Hill, and also occurs in the lowest zone of the 

 Sands, and again in greater numbers in the highest bed of the Lias both in 

 Yorkshire and Somersetshire, the specimens are found at the upper 

 boundary of this bed. 



Ammonites variabilis, d'Orb. A. Beanii, Simpson. The name selected 

 by d'Orbigny is not very appropriate as the characters of the species are 

 very constant, the young shells are tumid, and when their diameter does 

 not exceed an inch they are difficult to distinguish from the young of 

 A. insignis ; in the aged condition, when the ornamentation has disappeared, 

 the figure becomes much more discoidal and the keel very narrow and 

 prominent, so that it is usually broken away. This is strictly a boundary 

 species, the uppermost bed of the Upper Lias and the lowest zone of the 

 Sands appear to constitute its limits. Aged discoidal examples constitute 

 the A. obliquatus of Simpson. 



Ammonites Jimlriatus, Sow. A few young examples of this well-known 

 species have occurred in the lower zone of the Sands at Nailsworth, the 

 test has perished but the ornaments upon the surface are more or less 

 preserved. 



Ammonites crassus, Phillips, syn. A. Raquinianus, d'Orb. This Upper 

 Lias species occurs in a dwarfed form but in tolerable abundance in the 

 lower zone of the Sands at K'ails worth and at Brimscombe in the 

 Cotteswolds. 



Ammonites Ilminsterensis, Lycett. Another Upper Lias species allied to 

 A. crassus and occupying the same geological position both in the Lias and 

 the Sands. 



Ammonites complanatus, Bruguiere, A. elegans, Sow, A. exarattcs. Young 

 and Bird, A. licarinatus, Miinster, A. depressus, Buch. This beautiful species 



• A. insignis, Schiib., has been found in the Upper Lias Clays at Ununster. T. "W". 



