CEPHALOPODA. 
4G7 
preservation, with the septa obscure, it bears much resemblance to G. sinuosus, 
but may be distinguished by the outer volution overlapping the inner ones to 
a greater proportionate width, and a comparatively greater expansion of the 
chamber of habitation. It is readily distinguished from all the other species 
known to us in the New York formations. 
Formations and localities. This species is known in the shales of the Portage 
group, on Paterson’s creek, near Moscow, N. Y.; at Gibson’s Mill, near the 
Genesee river, above Mount Morris; and above the lower Portage Falls, near 
Portageville. It also occurs in the lower part of the Chemung group, at Pine 
Yalley, in the town of Catharine, Schuyler county, N. Y. 
Goniatites Chemungensis. 
PLATES LXIX, FIG. 9 ; LXXIV, FIG. 6. 
Goniatites Chemungensis. Vanuxem. Geolog. Surv. of N. Y. : Rep. Third Dist., p. 182, fig. 1. 1842. 
“ “ “ Hall: Illustrations of Devon. Fossils: Cephalopoda, pi. 69, fig. 9. 1870. 
Shell discoid, expanded. Inferring from the condition of the compressed speci¬ 
men, the transverse section of the tube has not exceeded one-fourth that of 
its lateral diameter. 
Volutions gradually expanding, about four (or five?); all exposed in the 
wide, shallow umbilicus; the inner ones partially embraced in the outer. 
The transverse section is'broadly oval, and a little sinuate, or somewhat 
expanded -in the middle of the sides of the outer one ; rounded upon the 
periphery, and concave on the umbilical side. The # enlargement of the 
volutions is very gradual; the base of the air-chamber, at the end of about 
the fourth volution, measures a little more than thirty mm. The inner 
volutions are not in a condition to be measured. 
The chamber of habitation, known only at its commencement, is continued 
in the same proportions as the preceding chambered portion of the shell. 
Aperture unknown. Air-chambers numerous; the width of the volution 
is equal to about three chambers in their greatest depth, and nearly twice as 
many at the umbilical margin. 
