ORDOVICIAN FAUNAS. 185 
as a member of the genus Hecyliomphalus by Ulrich and Scofield, 
but the New Jersey specimens are certainly cogeneric with the species 
referred by them to this genus, and there also seems to be no question 
as to their identity with the shells described as Cyrtolites trentonensts 
from New York. 
ECCYLIOMPHALUS contTIGUUS Ulrich. 
Plate XII., Figs. 13-15. 
1897. Hecyliomphalus contiguus Ulrich, Pal. Minn., pt. I1., p. 1037, 
pl. 74, figs. 48-52. 
Description—‘Shell 12 to 30 mm. in diameter, 7 to 16 mm. in 
height, consisting of three or four rapidly-enlarging, contiguous 
whorls, coiled so as to leave a deep umbilicus, in which from a third 
to a half of each of the inner whorls is visible; whorls subovate in 
section, higher than wide, somewhat narrowly rounded in the outer 
half of the upper surface. On the upper side the inner whorls may 
be sunken slightly beneath or raised above the level of the last; inner- 
most whorl with a free termination. Mouth obliquely subovate, the 
margin rather deeply notched above, broadly curved forward on the 
outer side and gently sinuate below. Surface markings somewhat 
irregular and coarse, parallel with the edge of the mouth.”—UIrich. 
Remarks.—A single specimen from the Trenton limestone of New 
Jersey seems to be identical or at least closely allied to #. contiguus, 
described by Ulrich from the Stone’s River group of Tennessee. It 
is smaller than the dimensions recorded for the Tennessee shell, having 
a maximum diameter of only about 6.5 mm., but this may be due 
to the immaturity of the shell. The shell itself is apparently entirely 
removed from the specimen, so that the surface markings and the 
outline of the aperture cannot be certainly determined, but the gen- 
eral contour of the shell agrees closely with Ulrich’s figure 52, except 
that the New Jersey shell is slightly lower. If sufficient material could 
be examined, it is possible that the New Jersey specimens would con- 
stitute a species distinct from, but closely allied to, this species de- 
scribed from Tennessee. 
