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long as the principal lateral. The form of the inner whorls of 
Scaphites corresponds with those of Olcostephanus. Mouth- 
border round or oval, provided with large protuberant bands, 
more or less prominent. All the species are found in the 
Cretaceous rocks. Scaphites gigas, Sow., fig. 72. I have 
collected magnificent examples of this grand form in nodules> 
from eighteen inches to two feet long, in the Lower Greensand 
Fic. 72.—Scaphites gigas, Sowerby. 
at Whales Chine, near Black-Gang, Isle of Wight. Scaphites 
Ivanii, Puzos, fig. 71, is from the Lower Neocomian, and 
Scaphites, ceequalis, Sow., I have found in the Lower Chalk at 
Lewes, Sussex, and Chardstock, Somerset. This species is very 
abundant in the “ Craie chloritées inférieures” of France. 
Genus Hortites, Newum.—This genus is composed of a group 
of species which were formerly classed with Perisphinctes, and 
now separated therefrom, and characterised by having the shell 
closely involute with high whorls and a narrow umbilicus. The 
sculpture consists of numerous small undulating ribs, often 
polytomate (fig. 73), which arise, by a thickened stem or 
tubercle, from near the umbilical suture, and soon split up into 
smaller divisions; sometimes the ribs encircle the siphonal area, 
or are interrupted here either by their vanishing away at the 
border of the area or by a median channel, which breaks their 
continuity, or by a kind of crest formed by the abrupt termi- 
nation of the lateral ribs, as in Hopl. splendens, Sow., or the 
