ROBERT TRACY JACKSON ON ECHINI. 

 Table of Aberrant Ocular Plate Arrangement in 48,541 Specimens of the Centrechinoida. 1 



'This table includes all aberrant variants of the Centrechinoida listed in the tables, pp. 142, 143, 154 to 163. See text- 

 figs. HO, p. 114; 140-149, p. 134; 155, 156, p. 145; 177-179, p. 165; 182, p. 165; 196, p. 169. 



