140 
. bulbus. 
. cariosa. 
. Rudolphi. 
. succincta. 
. bitubercularis, 
. hemastoma. 
. callosa. 
. callifera. 
. scalariformis. 
. rugosa. 
ig? Baca ila ibe” Mila ela |i o Pel 
. engonata.* 
. brevidens.* 
lachalgefi ae] 
. lapilloidis.* 
P. macrostoma. 
CONCHOLOGY. 
P. tectum. 
5. Genus Monoceros. 
Animal. As above. 
Shell. 
argicks) fy 
aa MaMa Ba-Bas 
. textilosa. 
. lambosa. 
. lapillus. 
- cateracta. 
. fiscella. 
semi-imbricata. 
. deltoides. 
. trochlea. 
. vexillum. 
. distorta. 
. harpa.* 
. Floridana.* 
. dumosa.* 
PLE 
Differs only from the Purpura by a long, conical 
pointed, somewhat reflexed tooth in the outer lip. Five species. 
Monoceros cingulatum. 
M. imbricatum. 
Monoceros striatum. 
M. glabratum. 
M. crassilabrum. 
6. Genus Concholepas. 
Animal. 
Shell. 
Entirely unknown. 
Wide, rough, ovate; spire very short; aperture very 
Plea 
large, oval and sloped anteriorly ; the edges united, the right 
very thick and dentated ; muscular impression almost in form of a 
horse-shoe ; operculum horny and rudimentary. It was formerly 
considered a Patella, from which it differs by the operculum. One 
species. 
Animal. 
Concholepas Peruvianus. 
7. Genus Harpa. 
Unknown. 
Pl. XII. 
