MOLLUSCA. 
379 
TRIBE I.-AMMONACEA. 
With a sinuous septa, margin lobed and cut, meeting together 
upon the internal partition of the shell, and articulated by ser¬ 
rated sutures. 
Genus 6.—BACULITES. —Lamarck. 
Generic Character. —Shell erect, cylindrical, slightly com¬ 
pressed, and somewhat conical in some species ; partitions arti¬ 
culated by sinuous sutures; septa transverse, close, imperforate; 
lobed and lanceolate at the margin. 
Baculites Faugusii. — Faugus’s Baculites. 
Plate LXXXIII. fig. 3. 
Erect, cylindrical, opposite sides smooth and depressed; su¬ 
tures with lobed dentations. 
Genus 7. — TURRILITES.— Lamarck. 
Generic Character. —Shell spiral, turrited, volutions contigu¬ 
ous, and all conspicuous; partitions articulated with sinous su¬ 
tures ; septa transverse, lobed, and laciniated at the margin ; 
aperture nearly round. 
Turrilites costulata. — The Ribbed Turrilites. 
Plate LXXXIII. fig. 4. 
Erect, turrited; volutions convex, with transverse ribs, each 
with a tubercle at its base. 
Genus 8 .— AMMONOCERATITES.— Lamarck. 
Generic Character. — Shell horn-shaped, arcuated, subsemi¬ 
circular ; the partitions articulated with sinous, laciniate, branched 
sutures; septa transverse, sinous, imperforate; their margins 
lobed, laciniate; having a marginal tube or syphon, which does 
not perforate the septa. 
Ammonoceratites glossoidea. — The Glossy Ammonoceratites. 
Plate LXXXIII. fig. 5. 
Large, thick, cylindrical, arcuated, laterally depressed; inside 
flatly concave; apex compressed, tongue-shaped. Nineteen 
