41 267 Aricula n.sp. Shaly limestone Lower Helderberg grpp. Clarksville, N.Y. 268 Aricula textilis Hall. Shaly limestone Lower Helderberg group. Clarksville, N.Y.. 269 Grammya bisulcatum. Gonomphora hamiltonensis H. Aedromorpha mytiloides. Retimptea boydi, Len. Hamilton grpp. Platts Falls, N.Y. 270 Michelinia lenticularis, Hall. Shaly limestone Lower Helderberg grpp. Clarksville, N.Y. 271 Michelinia lenticularis, Hall. Shaly limestone Lower Helderberg group. Clarksville, N.Y. 272 Pentaculites gracanthus, Eaton, Pentaculite limestone Lower Helderberg group. Clarksville, N.Y. 273 Cimitaria recurva, Conrad. Hamilton grpp. Platts Falls. Orundosa Co., N.Y. 274 Favosites conicus, H Shaly limestone Lower Helderberg group. Clarksville, N.Y. 275- Favosites conicus, H. Shaly limestone Lower Helderberg grpp. Clarksville, N.Y. 276 Lichas Shaly limestone Lower Helderberg grpp. Clarksville, N.Y. 277 Mytilarea cordiformis Hall. Shaly limestone Lower Helderberg group. Clarksville, N.Y. 278 Mytilarea cordiformis, Hall. Shaly limestone Lower Helderberg group Clarksville, N.Y. 279 Mytilarea cordiformis, Hall ne Shaly limestone Lower Helderberg group Clarksville, N.Y. 280 Mytilarea cordiformis H. var. Shaly limestone Lower Helderberg group. Clarksville, N.Y.