| OCR Text |
Show 376 MR. H. ADAMS ON PERUVIAN SHELLS. [May 26 Fam. HELICINIDJL. 26. HELICINA (OLIGYRA) ZEPHYRINA, Duel. 27. HELICINA (OLIGYRA) ROTUNDA, D'Orb. Fam. PROSERPINIDJE. Genus CYANE, gen. nov. Testa imperforata, helicineeformis, depresso-globosa, nitida ; columella truncata; apertura sublunar is; perist. simplex, rectum. In Cyane the base of the columella is truncate, instead of being furnished with a spiral plait, as in Ceres and Proserpina ; and both the palatal and parietal laminae are wanting. It appears to be intermediate between Proserpina aud Proserpinella, in which latter genus, according to Mr. Bland, the columellar margin is quite simple. 28. CYANE BLANDIANA, sp. nov. (Plate XXVII. figs. 2, 2a.) C. testa depresso-globosa, tenui, diaphana, nitida, concentrice minutissime et confertissime punctulato-striata, lutea vel fulva ; spira convexo-conoidea, apice obtuso, sutura distincta ; anfr. 5, vix ultimo basi paulo convexiore, medio excavato ; apertura obliqua, sublunari; columella callosa, leviter arcuata, ad basin truncata ; perist. recto, tenui. Diam. maj. 8, min. 7, alt. 5^ mill. Fam. UNIONID^E. 29. ANODONTA (LAMPROSCAPHA) TENEBRICOSA, Lea. 30. MONOCONDYL.EA (PLAGIODON) SEMISULCATA, sp. nov. (Plate XXVII. fig. 3.) M . testa transversa, ovato-trigona, solida, ventricosa, valde ineequi-laterali; margine dorsali arcuato; margine ventrali sinuato; latere antico circulari; latere postico elongato, oblique ovato; umbonibus tumidis, incurvis, erosis; superficie vulvarum concentrice rugose striata, ad aream medianam radiatim sulcata, epidermide subrugosa olivaceo-nigra induta; intus margarita alba et iridescente. Long. 34, alt. 25, lat. 18 mill. An example of this species, but of larger size (the result probably of age), and in which the radiating furrows on the valves are almost obsolete, was before obtained by Mr. Bartlett, and in the list of the shells then collected by him, which I communicated to the Society, was referred to by me, with doubt, as M. (Plagiodon) isocar-dioides, Lea. On comparing, however, the specimens since obtained with Lea's figure and description in the Philadelphia ' Proceedings,' although possessing the same general character, they are, I consider, distinct, Lea's shell being much shorter compared with its altitude, and the surface of the valves being entirely smooth. |
