MEDINAN, NIAGARAN, AND CHESTER FOSSILS 
87 
Locality and formation.^ — Quarry half a mile northeast of 
Centerville, Ohio, in the argillaceous strata immediately beneath 
the Brassfield limestone. 
Nam.ed in honor of Dr. R. C. Hussey of Michigan University. 
Spyroceras microtextile Sp. nov. 
Plate XV, fig. 2 
Fragments of phragmacones 8 to 9 mm. in diameter, very 
slowly enlarging. At present elliptical in cross-section, formerly 
probably circular, or nearly so. Distinctly annulated, 5 annula- 
tions occurring in a length equal to the diameter of the conch at 
the point where the annulations are counted. In a specimen in 
which the total length of one of the annulations together with 
that of the groove above is 2 mm., the annulation occupies a 
length of almost 0.8 mm., the groove being 1.2 mm. in length. 
The surface of the shell is ornamented by very fine vertical and 
transverse lines, of which the former are detected more readily. 
Of the vertical striae there are 12 in a width of 1 mm.; of the 
transverse striae there are about 10 to 12 in a length of 1 mm., 
their number varying apparently more than in the case of the 
vertical striae. 
Locality and formation.' — Quarry | mile northeast of Center- 
ville, Ohio, in the argillaceous strata immediately beneath the 
Brassfield limestone. 
Remarks. — Judging from the description of Orthoceras textile 
Hall, the Centerville species is closely similar in ornamentation, 
but the annulations are relatively more numerous. Unfor- 
tunately, the type of Orthoceras textile is lost, so that it is im- 
possible to make closer comparisons. 
Ctenodonta cf. simulatrix Ulrich 
Plate XIV, fig. 19 
Complete shells about 8 mm. in length, with outlines similar 
to those of Ctenodonta simulatrix Ulrich, from the upper part 
of the Richmond near Spring Valley, Minnesota. However, 
nothing is known of its hinge teeth. 
