PLATE 19. 
1-7. Echinonéus cyclostomus LrEske. 
Valves of tridentate pedicellariae. 
1.— Stalk and head, valve B in the centre. Height of head 0.63 mm. 
2.— Valve A, 0.63 mm. interior view, profile. 
3.— Valve B, 0.62 mm. interior view. Of a single pedicellaria. 
4.— Valve C, 0.61 mm. exterior view. ¢ 
1-4 are taken from right posterior interambulacrum, near the actinostome. Alcoholic specimen, i 
measuring 19 mm. long. Fakarava Island, Paumotu Islands. 
5.— Valve B, 0.67 mm. interior view. 
6.— Valve C, fragment, exterior view, both from odd posterior interambulacrum, towards aboral end 
of anal system. Alcoholic specimen, measuring 23 mm. long. Fakarava Island. 
7.— Valve B, 0.54 mm. interior view, from adoral end of anal system. Alcoholic specimen with spines, 
measuring 26 mm. long. Barbados (?). 
Magnification precisely as on Plate 18. 
