CHAMA.—Ptats IV. 
Species 20. (Mus. Cuming.) 
CHAMA DivaRicatTa. Cham. testd orbiculari, subobliqua, 
prope umbones subtilissime divaricatim corrugato-stria- 
ta, deinde rugosa, squamis longiusculis fornicatis, spi- 
neformibus, erectis, profuse armatd ; valvarum margi- 
nibus interne crenulatis ; vivide ruft el purpureo-rufa, 
squamis eburneis, intus alba, margines versus purpureo- 
rufa. 
THE DivaricaTtE Cuama. Shell orbicular, somewhat 
oblique, very finely divaricately wrinkled with striz 
near the umbones, then rough and profusely armed 
with rather long spine-shaped erect vaulted scales ; 
margins of the valves crenulated internally; bright 
red and purple, scales ivory white, interior white, 
purple-red towards the margins. 
Hab. Catbalonga, Island of Samar, Philippines (attached 
to masses of coral) ; Cuming. 
This beautiful species may be recognized by the wrin- 
kled strize near the umbones; I cannot think that it is the 
result of accident, beg developed on that portion of the 
shell on which the sculpture deposited in an early stage of 
growth is most likely to be permanent. The spines which 
beard, as it were, the remainder of the valve are remarkably 
prominent and distinguished for their absence of colour. 
Species 21. (Mus. Cuming.) 
CHAMA FERRUGINEA. Cham. testé orbiculari, subobliqud, 
subrugosd, concentricée tenuilamellatd, lamellis appressis 
perpaucis anticis erecto-foliaceis, seriebus duabus pos- 
ticis ampliter foliaceis subappressis ; valvarum margi- 
nibus levibus ; albidd, ferrugineo-fusco hic illic pallide 
tinctd, lamellarum seriebus duabus posticis saturatioré 
Serrugineo-fuscis. 
Tur Rusty Cuama. Shell orbicular, somewhat oblique, 
concentrically finely lamellated, lamelle pressed down 
one upon the other, a few lamellz on the anterior 
side erectly foliaceous, two rows of lamelle on the 
posterior side, largely foliaceous and a little appressed ; 
margins of the valves smooth ; whitish, palely stained 
here and there with rust-brown, the two posterior rows 
of lamellee darker rust-brown. 
Hab. Bay of Honduras (attached to shells) ; Dyscn. 
An interesting new species recently collected by Mr. 
Dyson, which may be readily distinguished by the arrange- 
ment of its fine foliaceous lamelle and their peculiar rust- 
brown tint of colour. 
Species. 22. (Mus. Cuming.) 
CHAMA corNUcoPIA. Oham. testd crass, circuiter ovati, 
concentricé rude et irregulariter plicatd, mutica, valva- 
rum marginibus levigatis ; albidd, roseo pallide tinctd, 
intus intense purpured. 
THE CORNUCOPIA Cama. Shell thick, circuitously ovate, 
concentrically 1udely and irregularly plicated, free 
from scales or spines, margins of the valves smooth ; 
whitish, faintly tinged with rose, intense purple within. 
Hab. Red Sea. 
T cannot discover any trace of external sculpture in this 
species, it is of curious circuitous growth and from a 
locality which contributes very little to the genus under 
investigation. 
