214 ASPIDOBRANCHIA. EMARGINULAD. 
netted with encircling lines. Height one-eighth, length one- 
fourth of an inch. 
Inhabits the British sea on the southern coasts of Devon and 
Cornwall. , 
The species figured in Montague’s “ Testacea Britannica,” 
named Patella apertura, is not to be found in his collection ; 
but I have every reason to believe that it may belong to this 
Genus. 
2. Cemoria FLremineiana. Tab. X. fig. 4, 5. 
C. testa costis alternatim latis et angustis. 
Habitat in mari Orcadensi et Zetlandiensi rarissimé. Mus. 
D. J. Fleming et nost. in Mus. Brit. Long. +. Alt. 53; 
une. 
Shell with alternately broad and narrow ribs. Length one- 
fourth of an inch; height three-sixteenths. 
This highly interesting species was discovered in the Shetland 
Islands by my worthy friend the Rev. Dr. J. Fleming, who most’ 
kindly communicated to me the specimens from which this de- 
scription and figures have been made. 
FAMILY II. EMARGINULADA. 
Testa scutellato-conica ; vertice inclinato ; cavitate simplici ; 
margine posteriore fisso aut emarginato. 
Animal: tentacula duo, conica, oculis ad basin externam. 
Pallium amplissimum, marginibus replicatis, testam partim ob- 
tegens. Pes latus, crassiusculus. 
The shell flat-conic, its apex inclined ; its cavity simple; its 
hinder margin fissured or notched. 
The animal with two conic tentacles, the eyes placed at their — 
base ; the mantle very much dilated, its margins bent back, 
partly covering the shell; the foot is broad and thick. 
The organs of digestion, circulation and sensation differ not 
essentially from those of the Fissurelladze. 
