BRACHIOPODA. 469 
TEREBRATULA Patacontca (Gould). 
T. parva, solidula, albida, ovato-triangularis, sub-trilobata, quincuncia- 
liter punctata: valva opercularis plana; valva major convexa, sub-gib- 
bosa, costis tribus mediantis et utrinque costis quinque divaricantibus 
ornata; rostro brevi, marginibus inflectis ; foramine magno, rotun- 
dato: apophysts branchialis exilis. 
Terebratula Patagonica, Goutp; Proceed. Boston Soc. Nat. Hist., 
ii. 347. Dec. 1850. Expedition Shells, 97. 
SHELL small, solid, dirty white, ovate-triangular, somewhat trilobate; 
length and breadth about equal; small valve nearly flat, large valve 
deeply concave; surface finely sculptured in quincunx; large valve 
somewhat gibbous along the centre, smooth near the beak, with about 
fourteen rounded ribs, three of which are central ones along gibbosity, 
parallel, and about five divaricating submarginal ones on each side. 
Beak short, margins inflected ; ligament aperture large, rounded: upper 
valve sculptured in the same manner; branchial supports very delicate. 
Length one-third of an inch; breadth one-fourth of an inch; height 
one-fifth of an inch. 
Inhabits the coast of Patagonia. 
A smaller and less transverse species than the preceding, and the 
disposition of the ribs is quite different. It is also closely related to 
T. australs, but differs from it in the same respects. 
Figures 583, 583, lateral views of the shell; 583 6, edge of the 
shell, in outline; 583, details of sculpture, enlarged; 583d, 583 e, 
views of the apophysis. 
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