358 



Shell of an oblong oval form, rather depressed, slightly attenu- 

 ated behind, thick, rose-red, painted with paler radiating marks ; 

 valves nearly equal, smooth ; marginal Hne somewhat flexuous 

 reflected in front ; dorsal valve the larger, rather produced poste- 

 riorly, and truncated ; perforation very small, entire ; cardinal area 

 rather wide, with united deltidia, marked by a mesial groove; 

 ventral valve ovate, anteriorly slightly attenuated and rounded ; 

 its marginal line slanting downward from the apex on each side ; 

 internal appendage consisting of a single elevated rib, standing 

 out ; margin of the valves entire. 



!From Brazil, according to the late G. Humphrey. The pale 

 variety, f . 7 7, is from a specimen in Mr. Cuming^s Collection. 



30. Terebratula cancellata (pi. Ixxi. f. 93-95.) Kocli, vide 

 Kilster vii. i. t. 2. b. f. 11-13. 



Testa ovato-oblonga, ventricosa, fuscescente ; valvis valde inse- 

 ([ualibus, radiatim striatis, striis tenuibus confertissimis, Hneis 

 incrementi creberrime decussatis; valva dorsaH oblonga, postice 

 subacuminata, truncata ; foramine magno, circulari, integro ; area 

 cardinali rotundata, deltidiis majusculis, obsolete sulcatis, in medio 

 coalescentibus ; valva ventrali subovata, lateribus posticis antice 

 decHvibus ; linea marginal! flexuosa, margine valvarum exihssime 

 creindato. 



Shell ovate-oblong, ventricose, brownish ; valves very unequal, 

 radiately striated ; striae very slender, close-set, and very finely 

 decussated by the lines of growth ; dorsal valve oblong, acumi- 

 nated behind, and truncated ; perforation large, circular, entire ; 

 cardinal area rounded, with rather large, obsoletely grooved delti- 

 dia, united in the middle ; ventral valve subovate, with the poste- 

 rior sides inclining forward ; marginal line flexuous ; edge of the 

 valves very delicately crenulated. 



In ]\Ir. Cuming's Collection. 



31. Terebratula crenulata (pi. Ixxi. f. 96-98.) nohis. 



Testa suborbiculari, postice subacmninata, sub truncata, crassius- 

 cula, albicante, valvis insequalibus, radiatim costatis, costis paucis, 

 majusculis, rotundatis ; linea marginali flexuosa, antice subsinuata ; 

 foramine magno, subintegro ; area cardinali magna, subplanulata, 

 margine undulato ; deltidiis magnis, discretis ; valvse ventralis 

 margine postico ad utrumque latus declivi ; ossiculo interno e spina 

 valida obtusa, antice porrecta, ramulis duobus lateralibus retro- 

 versis ; margine valvarum crenato. 



