OCR Text |
Show 444 MR. H. ADAMS ON SHELLS FROM EASTERN PERU. [Nov. 22, 49. ANODONTA (LAMPROSCAPHA) ENSIFORMIS, Spix. 50. MONOCONDYLJEA (PLAGIODON) ? ISOCARDIOIDES, Lea. Fam. MYCETOPID^E. 51. MYCETOPUS SOLENIFORMIS, D'Orb. Fam. MuTELiDiE. 52. CASTALIA CORDATA, Humph. 53. LEILA GIGANTEA, Lea. 54. LEILA BLAINVILLIANA, Lea. 55. TRIQUETRA CORRUGATA, Lam. Several examples of this very fine species in most perfect condition. 56. TRIQUETRA OBLIQUA, Schum. Fam. ^ETHERIID^. BARTLETTIA, gen. nov. Testa libera, arquivalvis, inarquilateralis, clausa ; superficies valva-rum rugosa vel foliata, epidermide olivaceo-viridi induta. Cardo edentulus; ligamentum breve, crassum, prarcipue internum, laminis validis, curvatis, prominentibus suffultum ; impressiones muscu-lares duar, anterior elongata, angusta, posterior ovalis, ampla; linea pallialis simplex. Intus margaritacea. 57. BARTLETTIA STEFANENSIS, Moric. (PI. XXXVIII. fig. 7.) B. testa falcata, solidiuscula, antice irregulariter producta, angusta, torta, postice rotundata, margine ventrali valde sinuato, anteriore lobato; superficie valvarum antice irregulariter rugose plicata, postice angulata, concentrice crasse striata. Long. 75, lat. maj. 35, minor 20, alt. 27 mill. Etheria stefanensis, Moric. Journ. Conch, v. (1856) p. 178. This singular shell was first m et with by M . Porte in the Amazon, near its embouchure, and was described by M . Moricand as a species of Mtheria. M. Moricand supposed it to be adherent like the other species of that genus, and probably by a small portion of the surface of one valve near the beak, which was broken away in both of the specimens received by him. There are no traces, however, of any such adherence in the more perfect examples collected by Mr. Bartlett ; and the shell, not possessing this peculiarity, and differing also materially in other respects from JEtheria, forms, in m y opinion, the type of a distinct genus. The other differences to which I allude are:-the ligament being marginal like that of Anodonta, and not sunk in a groove of the area of one valve; the internal surface being without the blisters present in both the species of the African genus |