CONTRIBUTION TO 



meters in it? greatest diameter. Having a stout, wrinkled, epithecal crust on 

 the lower side. With a small scar at the base of attachment. Tubes unequal 

 in size, quadrangular or pentagonal in outline, from two to four millimeters in 

 diameter. Lineal furrows fine, distinct. Mural pores large, few in number, 

 and irregularly distributed . The diaphraghms are broken down in all the 

 tubes, and onl}' a faint impression is left on the walls. From these I would 

 judge they were moderately stout, and not much crowded. 



This is unlike any Michelinia that I am acquainted with, differing essen- 

 tiall}^ in the form of the tubes, and the large pores, and few in number, with 

 the wrinkled epitheca, makes it easily recognized from all other species. 



Found in the upper Devonian (Hamilton group), near Gibson's Station, 

 Clark county, Indiana. Now in the collection of the author. 



D O L A T O C R I X U S D E P R E S S U S , (S. A. Miller. ) 



Plate 2, Figs. 4-5-6. 



Species medium or below medium in size. Calyx depressed, bowl-shaped; 

 diameter about three times the height. Surface ornamented with radiating 

 lines, ridges and nodes. Radial ridges small, rounded, and have a node at the 

 center of each plate. Each interradial bears a central node, from which there 

 are radiating ridges, and on some plates there are a few scattering nodes. 

 Column about medium in size. 



Basal plates almost covered by the column. First primary radials a little 

 wider than long, bear an elongated central node from which there are small, 

 radiating ridges. Second primary radials quadrangular, very little wider than 

 long Tliird primary radials a little larger than the second, wider than long, 

 pentagonal, axillary, and, in the ray on each side of the azygous area, and in 

 the one opposite thereto bears upon each upper sloping side, a single secondary 

 radial, which is axillary and supports, on each upper sloping side, two tertiary 

 radials which arrangement gives to each of these three rays four, arms. In 

 each of the two lateral rays, the third primary radial supports, on one upper 

 sloping side, three secondary r'adials, and, upon the other, a single secondary 

 radial, whicli is axillary and supports, on each superior sloping side, two ter- 

 tiary radials, which gives to each of these rays three arms. There are, there- 

 fore, eighteen aniljulacral openings to the vault in this species 



The first interradials are large, have nine sides, and bear a prominent cen- 

 tral node from which there are radiating ridges of unequal size, the two larger 

 ones being directed toward the adjoining secondary radials. These radiating 

 ridges are more or less nodose. The second interradials are about two-thirds 

 as large as the first, and each one bears two nodes that sometimes coalesce and 

 form a transverse ridge. There are three small plates in the third range that 



