362 



parvis, longe discretis ; carina dorsali inconspicua, rotundata 5 valva 

 ventrali transversim oblonga, antice rotundata, postice in angulo 

 obtusissimo desinente ; sulco mediano subinconspicuo, rotundato ; 

 margine valvarum integro. 



Shell transversely subovate, thin, rugose, smooth, of a pale 

 colour ; marginal line somewhat flexuous, slightly sinuated in front, 

 dorsal valve of a somewhat tetragonal ovate form, very obtusely 

 angular behind and reflected ; perforation very large, incomplete ; 

 cardinal area large and flattened, deltidia small, very distant; 

 mesial ridge rounded, indistinct, ventral valve transversely oblong, 

 rounded in front, and finishing in a very obtuse angle behind ; 

 mesial groove rounded, indistinct ; margin of the valves entire. 



In Mr. Norris's Collection, and in that of M. Janelle. 



38. Terebeatula Labeadoeensis (pi. lxxi. f. 89, 90.) nobis. 



Testa suborbiculari, postice acuminata, obtusa, crassiuscula, 

 albida, valvis valde insequalibus, radiatim obsolete costatis ; bnea 

 marginali subflexuosa; valva dorsali antice rotundata, postice acu- 

 minata, obtusa ; foramiue magno, integro ; area, cardinali magna, 

 subplanulata ; deltidiis majusculis, coalescentibus ; carina dorsali 

 inconspicua; valva, ventrali suborbiculari, postice subacuminata, 

 margine valvarum crenulato. 



Shell suborbicular, acuminated behind, obtuse, thickish, whitish; 

 valves very unequal, obtusely radiately ribbed ; marginal line some- 

 what flexuous; dorsal valve rounded in front, acuminated and 

 obtuse behind ; perforation large, entire ; cardinal area large, some- 

 what flattened ; deltidia rather large, united ; mesial ridge indis- 

 tinct ; ventral valve nearly orbicular, slightly acuminated behind ; 

 margin of the valves crenulated. 



In the British Museum, from Labrador; C. Goodsir. 



39. Teeebeattjla Algoensis (pi. lxxi. f. 91, 92.) nobis. 



Testa suborbiculari, postice subacuminata, antice sublobata, 

 albida ; valvis radiatim striatis, carina dorsali conspicua, rotundata ; 

 foramine magno, incompleto ; margine valvse dorsali minutissime 

 crenulato. 



Shell suborbicular, slightly acuminated behind, rather lobed in 

 front, whitish; valves radiately striated; mesial ridge distinct, 

 roundish ; perforation large, incomplete ; margin of the dorsal 

 valve very minutely crenulated. 



A single valve of the species is in the British Museum, labelled 

 " Algoa Bay ; Bowerbank." 



