RESTORATIONS OF DEVONIAN CEPHALOPODS 469 
Gyroceras eryx Hall, n. sp. 
(Fig. 14) 
Description.—Shell large, regularly coiled, forming a very open spiral, making 
about one and one-half volutions. Regularly enlarging from near the apex to 
the chamber of habitation. Oval or circular in transverse section. Apex 
unknown. Greatest diameter of the coil 17 “™. 
Chamber of habitation comparatively short, and in one specimen appears to 
be contracted toward the aperture. Aperture not clearly shown, but apparently 
has a shallow hyponomic sinus on the convex side. 
‘Septa numerous, regular, with straight transverse sutures which near the 
chamber of habitation are g™™ apart on the convex side, and 5™™ apart on the 
inner side. 
Siphuncle small, situated about one-third the diameter of the shell from the 
lower side. 
What appear to be surface markings are preserved on the inner mold and 
show fine growth lines swinging backward and crossing the septa at an angle of 
about ten degrees. Fine irregular longitudinal lines which appear to be vestiges 
of color markings are also shown. 
Locality —Milwaukee Cement Quarry, Berthelet, Wis. 
