Although conodonts are known from widely scattered Lower Ordovician exposures in North America, most occurrences are poorly documented and are based on a few specimens from isolated samples. In the House and Confusion Ranges of western Utah, conodonts occur almost continuously through 2700 feet of Lower Ordovician strata. Five conodont faunas can be recognized in this succession and these serve as a standard for comparison with less continuous sequences elsewhere. The lowest fauna, in rocks traditionally interpreted as uppermost Cambrian, but now recognized to be of Tremadocian age, has been reported from southern Oklahoma and southern Mexico. The second fauna...