1867.] 301 [Hayden. 



cannot positively dotorniine the affinities of the animal represented 

 by these bones, but from their solidify of structure, and the cylin- 

 droid form of the ribs, we suspect Jsrh//)-ot/ii'n'um to be more nearly 

 allied to the Manatee than to any other known animal." 



"Though I have supposed the remains above described to indicate 

 the former existence of a mammal allied to the Manatee, they yet 

 appear to me of such singular character, that I have suspected they 

 may have belonged to an aquatic reptile, unlike any known, and per- 

 haps foreshadowing in its constitution the sea-cows, just as Iguano- 

 don appears to have foreshadowed the herbivorous pachyderms of 

 the Eocene tertiary period " A huge saurian has been indicated by 

 Dr. Leidy by remains found in this region, to which he has given the 

 name of Thespesius occidentalis. " Several vertebral, together with a 

 first phalangeal bone, from Nebraska, appear to indicate a deino- 

 sauri:in as colossal as the Ii/iKniodon of England, or the ILvh-ot^aurus 

 of New Jersey. Two of the specimens are exceedingly like mam- 

 malian lumbar vertebrEe, especially those of the elephant or masto- 

 don, and might readily be taken for such, were it not that they pos- 

 sess well-mai'ked processes for the articulation of chevron bones." 



The remains of two species of turtles were discovered not far from 

 Fort Rice, (Jumpsemya vicfus and Emi/a obscurus. Dr. Leidy also de- 

 scribes some very interesting fish remains from this portion of the Lig- 

 nite Basin, under the name of Mijloynathm priscus. "The very sin- 

 gular-looking fish, Chimcera, of the European seas, was represented 

 during the Miocene period in Nebraska, by a genus for which the 

 above name has been proposed. Its former existence is indicated by 

 specimens of dental plates, like those of Chimara, adapted to the 

 cru.-5hing of mollusca and Crustacea used as food. The specimens, 

 consisting of an upper maxillary and a premaxillary plate, were ob- 

 tained by Dr. Hayden from the Great Lignite Basin, near Long 

 Lake, Nebraska (now Dacota)." Dr. Hayden remarked that he re- 

 ferred to the fossils mentioned above, in order that the attention of 

 travellers might be directed to them, and that more abundant and 

 better specimens could be secured, that all doubtful points in regard 

 to their affinities might be cleared up. 



2. Dr. Curry describes what he calls a " Moss Rock." " This rock 

 can be found at a place known as Spring Lake, situated about ten 

 miles south of New Fort Sully, near the road leading from thence to 

 the old fort, and about three-fourths of a mile from and in sight of 

 the river (Missouri). It is about twenty feet high, and stands out 



