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Show 359 Professor Tuomey concluded that Morton's types represented two distinct species, and named the more elongated form represented by the annexed cut J. gibbus, regarding the other as the trne J. Barabini. At one time, I was inclined to think that this arrangement might be admissible in case Morton had included two types, and that they were both good species. A - more attentive reading of Morton's description, however, seems to me to show that he rather regarded the elongated or more oval form as the typical one, not only because he first refers to it in connection with the name i. Barabiniy but because he describes that species as " obliquely- oval", which would not be applicable to the rounder form represented by figures 2 and 2 a of our plate 3. That the Vancouver shell under consideration may be identical with the latter, I am inclined to believe; but still the question remains an open one whether either can be properly regarded as L Cripsii. In originally studying the form under consideration, I proposed to call it I. subundatus ; but, after seeing how widely I. Cripsii is supposed to vary by European authorities, I have concluded to refer our shell to it as a variety subundatus. Figure 3 of our plate 3 represents a specimen of somewhat different outline; still I think it belongs to the same species as figure 1 of the same plate. Locality and position.- Sucia Islands; Cretaceous. INOCEBAMUS 1 Plate 1, fig. 6. This is also a rather compressed left valve of an ovoid or subcircular shell, with a straight hinge, apparently about equaling half its entire length. It may possibly belong to the same species as the two forms already described, though it possesses stronger and more irregular as well as sharper concentric folds, and has a more obtuse beak, with a more regularly- rounded posterior margin. As it came from a different locality, however, and was found associated with an entirely different group of fossils, the probability is it belongs to a distinct species. Still the specimen is too imperfect to be positively identified with any known species, or described with any degree of confidence as new. I was at first inclined to think either this shell or the last might possibly be the more compressed valve of Inoceramus Vancouverensis, Shu-mard; but on examining more carefully his description in the Transactions of the Saint Louis Academy, I find the specimen described by him is also a left valve, and has a very gibbous, elevated beak. This being the case, none of the forms in the collection before me can, I think, be properly referred to that species. Locality and position.- Nanaimo, Vancouver's Island; Cretaceous. Genus TRIGONIA, Brugnifcre. TRIGONIA EVANSI, Meek. Plate 2, figs. 7, 7 a, 7 b. Trigonia Evansi, Meek ( 1857), Trans. Albany Inst, iv, 42.- Gabb ( 1304), California Geological Report, i, 189, pi. 25, fig. 17. Shell arcuate- subtrigonal, gibbous anteriorly, contracted, cuneate, and slightly gaping behind: ventral margin deeply rounded in outline in the middle; anterior side very short, rounding up nearly vertically No. 4 0 |