Published reports indicate that _T. s. spinifer_ is not abundant in some of the northeasterly parts of its geographic range. Adams and Clark (1958:10) wrote that few softshells at Long Point on the Canadian side of Lake Erie are "ever collected and the area's game keepers report ... (none) ... seen in recent years. They also tell of recurrent severe stormy winters in which the muddy bottom of the marshland was repeatedly churned up and frozen. Such climatic conditions could easily destroy a large part of the _Trionyx_ population overwintering in the mud bottom." Wright (1919:8) reported that softshells are "rarely seen" in bays on the New York side of Lake Ontario, and Babcock (1938:53) wrote that _spinifer_ "is not common in Lake Champlain." _T. s. spinifer_ probably extended its geographic range into the Hudson River drainage of New York _via_ the Erie Canal (connected Buffalo and Albany) after its completion in the early 1800's (DeKay, 1842:7). Now, the New York Barge Canal (essentially the Erie Canal, but with minor changes in course and the addition of several spurs) provides an avenue for dispersal of _spinifer_ to the Hudson River drainage, Lake Ontario and intervening waterways in New York (Mertens, 1928:199). Netting (1944:86-87), however, suggested that _spinifer_ occupied Lake Champlain, the Finger Lakes, Mohawk River and upper Hudson in the late stages of the formation of the Great Lakes. A publication not seen by me is that of Mansueti and Wallace (1960). Its title suggests that _Trionyx_ occurs in Maryland. The unsuccessful introduction of _T. s. spinifer_ in the Delaware drainage in New Jersey has been discussed by Fowler (1907:213), who wrote that they were found as early as the late 1860's and were introduced when young presumably to stock aquaria. Records of occurrence include Cooper's Creek, Camden County (Stone, 1906:168); Woodbury, Gloucester County (Cope, 1894:889); and Paulins Kill at Hainesburg, Warren County (Johnson, 1894:889). Surface (1908:122) believed that soft-shelled turtles "have doubtless been introduced into the eastern part of Pennsylvania through the canal from the Western and Central part of New York," and Roddy (_in_ Neill, 1951:21) suggested that the species may be found in the Susquehanna River. Babcock (1919:420) mentioned a young specimen of _spinifer_ in the collection of the Boston Society of Natural History that was obtained "in White River, Vermont," a tributary of the Connecticut River of the Atlantic Coast drainage; seemingly this record has not been accepted and the species is not established. To my knowledge, populations of _T. s. spinifer_ do not occur in rivers of the Atlantic Coast drainage, except probably the Hudson-Mohawk drainage.