58 



BATOCRINUS VABIABILI8, D. sp. 



Plate IV, Fig. 13, azygous side of a reguhir elongated speci- 

 men; Fig. 14, side view of same shoiving a four-armed 

 ray; Fig. 15, showing a four-armed lateral ray and 

 two plates in the regular interradial areas; Fig. 

 10, showing a four-armed ray, on the left of 

 the azygous area; Fig. 17, showing a 

 four-armed ray on the right of 

 the azygous area. 



Species variable in size, from small to medium; somewhat 

 biturbiuate, but varying in tbis respect. Calyx obconoidal, about 

 one-half wider than high. No radial ridges. First primary radials 

 and interradials varying from plane to nodose. Ambulacral open- 

 ings directed nearly horizontally and an ovarian pore by the side 

 of nearly every one of them. 



Basals form a round cup, about three times as wide as high; it 

 is slightly beveled to the column, which is about two-thirds 

 the diameter of the cup. First primary radials usually as long as 

 wide, three hexagonal, two heptagonal. Second and third primary 

 radials together smaller than the first. Second primary radials 

 (quadrangular, about twice as wide as long. Third primary radials 

 a little larger than the second, pentagonal, axillary, and in the 

 specimen represented by figures Vd and 14, the one on each side 

 of the azygous area bears upon the distal side two secondary 

 radials and upon the proximal side a single, axillary secondary 

 radial which bears upon each sloping side two tertiary radials, 

 which gives to each of these lays three arms. The left lateral 

 ray is constructed in the same way, except there is only a single 

 tertiary radial where the other rays have two, and it has, there- 

 fore, three arms. In the right lateral ray, as shown in figure 14, 

 there is a single, axillary, secondary radial, on each side of the 

 third primary radial, which bears upon each upper sloping side, a 

 single tertiary radial, which gives to this ray four arms. In the 

 ray opposite the azygou.s area, the third primary radial bears upon 

 each upper sloping side two secondary radials, which gives to it 

 two arms. There are, therefore, fifteen arms in this species. The 

 arm formula, in the specimen represented by figures 13 and 14, is 

 o-|-4+2+3+3. The specimen represented by figure 15 is con- 

 structed in the same way, except the left lateral ray has four 

 arms, and the arm formula is 3+3+2+4+3. The specimen rep- 

 resented by figure 1(!, has the ray on tbe left of the azygous area 

 bearing four arms.'and the arm formula is 3+3+2+3+4. The 



