| OCR Text |
Show 414 APPENDIX B.- PALEONTOLOGY. edge of the last volution, which has scarcely a distinct carina; upper margin of the volutions, along the suture, marked by an elevated nodulose ridge, giving a beautiful coronate feature to the upper part of the shell. Umbilicus, none. Fig. 6 a, view of the upper surface of the shelL Fig. 6 b, view of th£ aperture, which is imperfect. Fig. 6 c, anterior view of the shell. Fig. 6 d, base of the shell. This beautiful species was found with other carboniferous fossils. EUOMPHALUS SUBPLAKUS, Hall. ( n. sp.) PLATS IV. Fio. Tab. Spiral, convolute; volutions about five, in contact, round, or very obtusely sub- angular on the upper outer margin of old specimens, surface evenly striated. In young specimens the apex is depressed, but in the specimen figured it is slightly above the outer volution. The specimen fig. 7 b is the under side of a cast of an individual of apparently the same species, the absence of the shell leaving the volutions not in contact. Fig. 7 a, view of the upper side of a specimen from limestone on the top of Stansbury's Island, Great Salt Lake. Fig. 7 b, a cast in limestone from between the Big and Little Blue Rivers. |
