104 
by lines of growth : it is twice as long as wide, and not 
remarkably deep. The ligament is seated in a deep and 
wide groove. 
Only two specimens of this curious shell, which forms 
an osculent Genus, have fallen under our notice ; the one 
a young individual presented by G. W. Braikenridge, 
Esq. the other apparently full grown, purchased by 
Mr. G. B. Sowerby ; they are both from Dundry, near 
Bristol, and were imbedded in the Ironsliot Oolite. 
