TRIBE BRACHIOPODA. 331 
well-defined lateral ridges; perforation incomplete; deltidia small ; 
area flattened; lower valve rather flat; loop elongated, doubly 
attached ; septum produced, nearly touching the opposite valve. 4. 
N. Zealand.4 
T. Crenuntata. Sow. Th. 1, p. 858, t. 71, f. 96, 7,8.—Koch im 
Kust. vii. 1, t.2, b, f.11, 2, 3 ?>—Trrepratetia C. Davids. (no desc.). 
—? Mageas C. Gray, Brach. p.99. Suborbicular, inequivalve, rather 
attenuated and subtruncated dorsally, rather thick, whitish, with a few 
rather large rounded radiating ribs ; margin crenated, flexuous, slightly 
sinuated ventrally; perforation large, nearly entire; hinge-area large, 
flattish, with an undulated margin; deltidia large, separate. Dorsal 
edges of the lower valve sloping; internal appendage consisting of a 
single strong spine projecting towards the ventral margin, from whence 
emanate two lateral reflected branches. 4. Santa Cruz. 
T. Troncata.—Anomia T. Lin. 1152.—Ch. f. 701.—W. t.11, f.17. 
—A. Discuuus, Pallas. Mis. 7.—T.T. Lam. 11.—Phil. 1, p. 95, t. 6, 
J. 12 (in 2 as Ontuts T.).—Sow. Th. 1, p. 354, t. 71, f. 64 to 67.— 
Meeeruia T. Gray, Brach. p.103.—Woodw. t.15, f.9. Transversely 
suborbicular, subequivalye, depressed, truncated and very wide dorsally, 
brownish, with a nearly straight hinge-line, and fine radiating striz : 
margin entire, slightly sinuated ventrally. Perforation large, incom- 
plete; hinge-area elongated-triangular, flattened, with minute incon- 
spicuous deltidia; mesial ridge small. Lower valve rather flattened, 
straight dorsally, with a small mesial notch; mesial groove rather 
broad, not very distinct; loop short, doubly attached, and giving off 
from its reflected portion two additional processes to the central 
septum: internal surface with small close-set radiating granules. 
4...4. Mediterranean.” 

t This, the succeeding, and the TErEBraTeLta? Cuminair of 
Davidson (7%. P. 1852, t.14, f. 10 to 16.—M. C. Gray, Brach. p. 99) 
are referred by Gray (not by Davidson) to the subgenus Macas (of 
Sowerby). The last-named species is thus described :—“ Oval, thick, 
smooth, white, slightly tinged with red; beak produced, tapering, 
slightly curved, grooved to the summit; area triangular, concave ; 
deltidium obsolete ; lower valve with a prominent muscular fulcrum ; 
loop doubly attached; septum elevated, reaching the upper valve. 
yr. N. Zealand. 
2 This and T. Puncuerta are the only recent species of the 
subgenus Muaeuriia. “ Transversely oblong, with a wide and rather 
straight hinge-line; area distinct; foramen incomplete ; loop rather 
short, reflected, trebly attached to the hinge-plate, once by its crura, 
and twice to the septum.” 
