20 HAWAIIAN AXD OTHER PACIFIC ECHINI. 



spines and are carried upon tubercles which might truly be called niiliaries. 

 The secondary tubercles form a ring of a single row round the scrobicular 

 area; the rest of the interambulacral plates is occupied by miliaries both in 

 the median interambulacral space and in the space adjoining the poriferous 

 zone. This granulation resembles somewhat that of Chondrocidaris 

 gigantea. The median ambulacral space carries only very small miliaries 

 forming irregular, interrupted, vertical rows between the two vertical rows 

 of larger ambulacral secondaries. 



This arrangement is only well developed in the larger specimens ; it is 

 only apparent in specimens as large as those figured in PL 26, figs. 1-.^, and 

 fully developed in larger specimens. 



There is only a single vertical row of narrow, elongate actinal interam- 

 bulacral plates. 



Besides the radical differences in color, this species may be distinguished 

 from >S'. bispinosa by the much longer and more slender primary radioles 

 and the large actinal system, which is but little, if at all, smaller than the 

 abactinal. 



The large globiferous pedicellariae seem to be entirely wanting, and in 

 young individuals the tridentate are also quite infrequent. 



The tridentate pedicellarioe (PI. 4, figs. 22-23) have valves long and 

 slender, as much as 1.5 mm. in length, while the stalks are more or less 

 nearly equal to them. Tliey occur chiefly on the interambulacra about the 

 prnnary spines, and are quite common in large individuals. 



The small globiferous pedicellariae (PI. 4, figs. 20-21) are not peculiar, 

 but the valves have a prominent end-tooth. The valves are about .50 mm. 

 in length and are borne on stalks from one to six times as long. These pedi- 

 cellariae are common, especially on the abactinal system of the young and 

 the interambulacra of the adults. 



This species was collected by the '' Albatross " at the following localities. 



Station 3845. Off Lae-o Ka Laau Light, S. coast of Molokai. Bott. 

 temp. 71\ 00-64 fathoms. Crs. s. p. sh. 



Station 3846. Off Lae-o Ka Laau Light, S. coast of Molokai. Bott. temp. 

 7L5°. 00-64 falhouis. Crs. l)r. s. A\. <-. 



Station 3849. OlY Lae-o Ka Laau Light, S. coast of Molokai. Bott. temp. 

 07.6". 43-73 fathoms. Crs. s. br. sli. co. 



Station 386L Pailolo Channel and N. E. approach. 30-52 fathoms. Fne. 

 p. sm. p. CO. 



