48 



diately sculptured from the central part of each plate, but with- 

 out any central nodes or other elevations. Arm openings di- 

 rected upward at an angle of about forty five degrees. Column 

 round, rather large and having a large, slightly cinque-foil 

 canal. 



Basal plates form an hexagonal disc about one-third wider 

 than the diameter of the column. The first primary radials 

 are the largest plates in the calyx, slightly unequal in size, 

 not visible in a side view, those abutting on a single basal are 

 heptagonal. The second primary radials are hexagonal, wider 

 than long, differ somewhat in size, but smaller than the first. 

 The third primary radials are slightly smaller than the second, 

 the two adjoining the azygous are hexagonal, the other three 

 are heptagonal. They are all axillary and bear the secondary 

 radials. There is a single secondary radial on each upper 

 sloping side of the third primary radials in the two rays ad- 

 joining the azygous area and in the ray opposite thereto. 

 Each of these secondary radials are axillary and bear upon 

 each superior sloping side two tertiary radials which gives to 

 each of these three rays four arms. In the two lateral rays 

 there are three secondary radials in each series which gives 

 to each of these rays two arms. This arrangement gives to 

 the species sixteen arms. 



In each of the intersecondary areas that separate the three 

 four armed series there are two plates, one following the other, 

 the second one unites with the plates of the vault which throws 

 the arms together in eight pairs. In each regular interradial 

 area there are ten plates, the first one is hexagonal, rests be- 

 tween the upper sloping sides of the first primary radials, 

 separates the second primary radials and is followed by two 

 smaller plates in the second range, three in the third range, 

 two in the fourth range and two in the fifth range, that sepa- 

 rate the last tertiary radials and unite with the plates of the 

 vault. The azygous area is large and contains twenty two 

 plates. The first one is in line with the first primary radials 

 and about as large; it is followed by three plates in the sec- 

 ond range, five plates in the third range, four plates in the 

 rourth range, four plates in the fifth range, three in the sixth 

 range, and two in the seventh range that separate the last 

 tertiary radials and unite with the plates of the vault. 



