74 



AMMONITES corrugatus. 



TAB. CCCCLl.— /^. 3. 



Spec. Char. Discoid, carinated and iimbili- 

 cated, strongly radiated ; carina distinct ; 

 radii waved, sometimes furcated, elevated ; 

 umbilicus broad, exposing parts of the inner 

 whorls ; aperture obovate ; front obtuse. 



Resembling the last, but thicker, with more prominent 

 radii, and a broader front. 



From Dundry, with the A. laeviusculus. 



AMMONITES varicosus. 



TAB. CCCCLL— /^5. 4 and 5. 



Spec. Char. Depressed, costated; inner vo- 

 lutions exposed ; carinated when young, 

 and furnished with an irregular row of tu- 

 bercles upon the inner edges of the whorls ; 

 costae curved, large, obtuse, in old shells 

 crossing the front; carina distinct; aperture 

 oblong. 



J-N the very young state this Ammonite like many 

 others, appears to be nearly plain, but has a distinct 

 carina ; as it grows older, a series of crescent shaped, 

 nearly close ribs appear on each side of the keel, and a 

 few small tubercles arise upon the inner edges of the 



