John M. Legler

“ As more specimens of Geophis become available from intermediate localities in Mexico, it will perhaps be demonstrated that many of the kinds now thought of as full species (including those discussed above) are subspecies of a few wide-ranging species.
Remarks.—The type locality of G. aquilonaris is the small village of Barranca at the bottom of the valley of the Río Urique, several miles south and west of the continental divide. ”

“ The markings of the three smaller paratypes are substantially the same as those of the holotype—complete rings with a small number of variations in each specimen. In the two largest paratypes nearly all the white rings are incomplete ventrally, appearing to have been encroached upon by the darker ground color. In the larger speicmens there is a tendency also for the white rings to be one scale wide (rather than alternately one and two scales wide) and to lack a zigzag appearance; this appears to be due to the darkening of entire scales and to the darkening of the edges of other scales. ”

“ Head slate-black above, having dim pale mark on anterior part of each prefrontal and another on interparietal seam; an indistinct pale gray crescent on posterior border of nostril; narrow cream band covering posterior edges of parietal and half of first dorsal scale row, widening laterally to include temporal and posterior two or three supralabials; throat cream (except for dark markings on mental, on first three infralabials, and on anterior chin shields) , its pale area continuous with pale band on head; body and tail marked with alternating white and black rings ”