13 3. 
176 MR. G. F, ANGAS ON NEW AUSTRALIAN SHELLS. [Mar. 6, 
Gen. Mysetua, Angas, 
Shell small, thin, equivalve, inequilateral, quadrately cuneate, 
concentrically striated. Hinge with a small triangular internal car- 
tilage-pit, close to which is a single small, diverging, subcircular, 
flattened cardinal tooth in one valve, and with two thin short hori- 
zontal lateral processes in the other vaive. Siphonal inflection none. 
MyseLLA ANOMALA, n. sp. (Plate XXVI. fig. 22.) 
Shell somewhat triangularly ovate, compressed towards the base, 
rather thin, anterior side shortest, white, covered towards the edges 
with a pale brown epidermis, concentrically very finely and regularly 
ridged ; dorsal margins nearly straight, anterior side somewhat com- 
pressed and subtruncate; posterior side rounded; ventral margin 
scarcely convex; umbones a little tumid; beaks small, incurved, 
approximate. 
Long. 5, alt. 4, lat. 2 lin. 
Hab. Shark Island, Port Jackson, in black mud, 12 fathoms 
(Brazier). 
CyTHEREA SOPHIA, n. sp. (Plate XXVI. fig. 23.) 
Shell small, roundly ovate, tumid, moderately solid, irregularly 
concentrically striated with the lines of growth, shining, white, 
painted with a narrow longitudinal band of irregular bright-chestnut 
markings on the anterior side of the valves, and a broader one of 
larger markings on the posterior side, leaving a white ray in the 
centre ; umbones tinged with yellow and carnation-red; lunule 
distinct. 
Long. 6, alt. 5, lat. 4 lines. : 
Hab. Cape Solander, Botany Bay, after an easterly gale (Brazier). 
The small size, rounded form, and rich colouring of the umbones 
lead me to consider this shell a distinct species from any of its 
allies. I have much pleasure in naming it after Mrs. Brazier. 
Lucrna (CopAk1A) QuADRATA, n. sp. (Plate XXVI. fig. 24.) 
Shell quadrately ovate, moderately solid, subventricose, very in- 
equilateral, yellowish white, very finely concentrically striated 
throughout, the striae becoming slightly undulating and scabrous to- 
wards the base, where they are crossed on either side by broader 
radiating flattened ridges; dorsal margin concavely excavated ante- 
riorly, nearly straight and rapidly descending posteriorly ; ventral 
margin arcuate, rounded in front ; umbones acute, incurved, approx- 
imate; dorsal area excavated. 
Long. 2, alt. 13, lat. 1 lin. 
Hab. Shark Island, Port Jackson. 
KeELLIA SOLIDA, n. sp. (Plate XXVI. fig. 25.). 
Shell somewhat quadrately ovate, rather tumid, inequilateral, 
anterior side the shortest, solid, opaque, white, shining, smooth and 
polished at the umbones, showing irregular concentric lines towards 
the base; umbones small, distinct, approximate; anterior side 
