Large Newfoundland Tarphys

 
The New Mexico Museum of Natural History and Science in Albuquerque NM has in its fossil collection a number of large tarphycerids, an order containing the earliest coiled nautiloid cephalopods, from Newfoundland, Canada, originally belonging to the late Dr Rousseau Flower.   Two,  Loganites and Bennettoceras, were named by him but descriptions are lacking.  Others presumed also to be from Newfoundlland are unidentified.  
                        
                                                                                
Loganites, upper left,  Bennettoceras, middle left, and a large unnamed tarphycerid, bottom right.  All are external views.  Much of the matrix was artificially stripped away using Photoshop. Loganites is on the order of 7 in in diameter ( about 18 cm),  Bennettoceras is somewhat smaller, about 5 in ( 12.5 cm).   The straight portion of the unnamed specimen is about 7 in (18cm) as well.   All are internal molds.  All are Ordovician in age

A barrandeocerid section

Shown here is a section of a barrandeocid,, housed in the collections of the New Mexico Museum of Natural History and Science,  Albuquerque, NM, http://nmnautralhistory.org.  The specimen, P-56465, is about 8 cm long (about 3 in.).

The interpretation is mine, based  on the close spaced septa and narrow tubular siphuncle.  I have yet to assign a genus name. Location is unknown, but based in the overall color and general texture I'd say it came from the Ordovician of northeastern North America, most likely Newfoundland. 

The first picture, on the left, shows the overall specimen , what's left of it, an arc segment of one of the whorls. The second , below,, shows the specimen in greater detail with the septa and narrow, tubular siphuncle, located slightly below the center, clearly shown.