142 MR. BRODERIP’S DESCRIPTIONS OF SOME NEW SPECIES OF 
bisecting it, and the thickness from another imaginary line, supposed to be drawn 
through the middle of the two valves and the included space. 
Mr. Cuming found this Terebratula in the Bay of Valparaiso, at a depth ranging from 
sixty to ninety fathoms. The older shells were attached to rocks, and the younger to 
Corallines and Fuct. 
2. TereBRATuLA Uva. 
Tab. XXII. Fig. 2. 
Ter. testd ovato-oblongd, ventricosd, subglabrd, subdiaphand, lineis concentricis substriatd ; 
valvd perforatd subelongati. 
Long. 1 poll., lat. s, diam. +7. 
Hab. in sinu Tehuantepec. 
Mus. Cuming. 
This Terebratula was found by Captain Dare, while dredging for Meleagrine margari- 
tifere, attached to a dead sea-worn bivalve, at a depth of from ten to twelve fathoms, 
and on a bottom of sandy mud. 
Genus. Orspicua, Cuv. 
1. OrpicuLa LAMELLOSA. 
Tab. XXIII. Fig. 2. 
Orb. testd corned, fuscd, suborbiculari, subdepressd, lamellis concentricis elevatis rugosa. 
Long. 1-4, poll., lat. 1. 
Hab. ad Peruvie oras. (Iquiqui.—Bay of Ancon.) 
Mus. Cuming. 
This species was found by Mr. Cuming in groups, the individuals being in many 
instances piled in layers one over the other on a sandy bottom, at a depth ranging 
from five to nine fathoms. At Ancon they were found attached to dead shells, and 
also clinging to the wreck of a Spanish vessel of about 300 tons, which went down in the 
Bay about twelve years ago. The sunken timbers (for the sheathing was gone to decay,) 
were covered with these shells, much in the same way that beams on land are some- 
times invested with flat parasitic Fungi. At Iquiqui they were taken adhering to a 
living Mytilus. 
It is to be observed, that the bearded appearance round the border of many of the 
specimens is produced by the dried remains of the cilia of the mantle. The lower valve 
varies very much according to circumstances, being thinnest and smoothest when it is 
least exposed: in those instances where the adhesion is co-extensive with the surface, 
it is very thin. Generally it is convex where it rises from the depressed area of the 
perforated part ; but this convexity depends so much on position and other accidental 
circumstances, that it cannot be relied on with any safety as a character. 
The measurement merely relates to the extent of surface of the upper valve, the 
