306 



NORTH-CAROLINA GEOLOGICAL SURVEY. 



FIG. 238. 



small tubercles with two in a row, and interspersed with 



minute ones, which appear in 

 some places to be arrayed in sub- 

 ordinate rows ; interambulacral 

 areas wide, covered with small 

 subequal and rather prominent 

 tubercles, among which minute 

 granules are scattered ; area about 

 four times as wide as the former ; 

 plates pentagonal, supporting two 

 rows of large perforated primary 



tubercles, surrounded by plain circular zones ; miliary zone 

 concave or depressed. Poriferous zones narrow ; pores uni- 

 geminal; outer oblong; the inner circular; margin of the 

 small plates between them marked with an elongated depres- 

 sion. The upper and lower sides crushed. 



Belongs to the eocene, and accompanies the former. 

 Figure 105 represents the jaws of an Echinoderm, p. 246. 

 The separate pieces of the test and jaws are quite common 

 in an eocene bed in Craven county. They belong to the 

 upper part of the bed, and seem to be confined to a space 

 about two feet thick. 



FAMILY CIDARITAS. ECHINUS RUFFINII. ED. FORBES. (Fig. 239.) 



u Body sub-depressed ; ambulacral and interlambulacral ; 



plates with several primary tu- 

 bercles on each closely ranged, 

 having circles of secondary tu- 

 bercles surrounding their bases; 

 rows of pores very oblique, 

 with three pair of pores in each 

 row, the uppermost distant from 

 the other two. Beneath con- 

 cave ; mouth broad ; widely 

 notched opposite each avenue.' 7 

 Ed. Forbes.* 



FIG. 239. 



Journal Geological Society, vol; i, p. 426< 



