In Eutamias the baculum is broad at the base and the shaft tapers distally to the junction of the shaft and tip, or the base is only slightly wider than any part of the shaft.
"Genera and Subgenera of Chipmunks"
John A. White
Lepidotrichia jointed distally, but not tuberculated.
"A New Genus of Pennsylvania Fish (Crossoperygii, Coelacanthiformes) from Kansas"
Joan Echols