189 
12. UmBoniuM ZELANDICUM, A. Adams. JU. testa orbiculato- 
conoidea, imperforata; spira elata, anfractibus quinque, exca- 
vatis, transversim striatis, ultimo subangulato, ad peripheriam 
sulcato, suturis anguste marginatis ; albida, cupreo-nitente, 
lineis fuscis, undulatis, longitudinalibus, radiatim picta ; infima 
facie planiuscula, striata, albida, cingulo cinereo circa umbili- 
cum ornata; callo mediocri umbilicum obtegente, externe sulco 
spirali impresso ; apertura ovali ; labio incrassato. 
Hab. New Zealand. Mus. Cuming. 
Subgenus Eruattia. 
Shell orbicular, turbinately depressed ; whorls smooth or trans- 
versely striated, convex, rounded at the periphery ; umbilicus partly 
closed by a callous deposit. 
13. Umspontum GuaMENSsE, Quoy & Gaimard. 
Rotella Guamensis, Quoy & Gaim. Voy. Astrol.; Kien. Mon. Ro- 
tella, pl. 2. fig. 2. 
Hab. Island of Guam (Quoy §& Gaimard); Philippine Islands 
(Cuming). Mus. Cuming. 
14. Umsonium srriotatum, A. Adams. U. testa discoidea, 
subglobulosa, subperforata, transversim striata, anfractibus 
quinque, convexiusculis ; lineis transversis, angustissimis, albido- 
articulatis ornata; infima facie levi, ad peripheriam rufo- 
Jusco maculata, cingulo rufo circa regionem umbilicalem ornata, 
callo albo, parvo, umbilicum partim obtegente munita; aper- 
tura ovali. 
Hab. Island of Borneo. Mus. Cuming. 
12. A MonocGrar# or Isanpa, a New Genus oF TROCHIDA, 
ALLIED TO UmsBonium. By Artruur Apams, F.L.S. Etc. 
Genus Isanpa, H. & A. Adams. 
Shell porcellanous, orbiculately conoidal, polished ; aperture sub- 
quadrate, inner lip straight, forming an angle with the outer lip; 
umbilicus open, perspective, the margin crenulated. 
In this genus, which is founded on three undescribed species of 
shells, the umbilicus is open, and not covered by a callous deposit, as 
in Umbonium, and the margin is crenulated ; the texture of the shell 
is solid and porcellanous, and not thin and nacreous, as in Margarita. 
Isanpa coronata, A. Adams. JT. testa orbiculato-conica, um- 
bilicata, levi, nitida ; spira obtusa, anfractibus quinque, planis, 
superne angulatis, et concinne crenulatis ; sutura canaliculata ; 
lineis albidis, transversis, et maculis fuscis, in sertebus trans- 
versis dispositis, et, ad suturas, fascia alba, lata, ornata; aper- 
