218 
plaited, with alternate broad, sharp edged and very fine spiral ribs; suture distinct. 
Mouth ovate; throat grooved, outer lip crenulated; canal elongated, tapering, transver- 
sely striated, smooth in front. 
Length 5 inches. 
Inhab. China; not uncommon. 
Compare with F. laticostatus Desh., but the rihs are not broad and depressed. 
The nucleus of this species, as in the most of the genus, is quite smooth, sub- 
cylindrica], blunt, of one whorJ and a half; the periostracum thin, pale, brown, 
hairy. 
