PLATE 21. 
1-20. Echinonéus cyclostomus LEskKE. 
Valves of ophicephalous pedicellariae. 
1.— Stalk and head, 0.63 mm. long, from left posterior interambulacrum, actinal side of ambitus. 
2.— Pedicellaria, 0.26 mm. valve C in centre, from right posterior interambulacrum. 
3.— Valve A, 0.25 mm. exterior view. 
4,— Valve B, 0.23 mm. interior view. 
5.— Valve B, 0.23 mm. interior view profile. Of a single pedicellaria. 
6.— Valve C, 0.22 mm. exterior view, from left posterior interambulacrum, 
actinal side of ambitus. 
7.— Valve C, 0.25 mm. exterior view. 
8.— Valve A, 0.28 mm. exterior view, from right posterior interambulacrum, | same pedicellaria. 
actinal side of ambitus. 
Figures 1-8. Dry specimen with spines measuring 34 mm. long. Lord Howe Island. 
9.— Valve B, 0.21 mm. interior view. 
10.— Valve C, 0.20 mm. exterior view, from left posterior interambulacrum 
towards apical system. Test with spines measuring 30 mm. long. 
Lord Howe Island. 
11.— Valve B, 0.16 mm. interior view. 
12.— Valve C, 0.15 mm. interior view, from left anterior interambulacrum, 
apicalsystem. Alcoholic specimen measuring 11mm.long. Fakarava 
Island, Paumotu Islands. 
13.— Valve B, 0.21 mm. interior view, from left anterior interambulacrum, midway between actino- 
stome and ambitus. Alcoholic specimen, with spines measuring 15 mm.long. Makemo Island, 
Paumotu Islands. 
14.— Valve C, 0.19 mm. exterior view, from right anterior interambulacrum, actinal side of ambitus. 
Test measuring 15 mm. long. Makemo Island. 
15.— Valve A, 0.32 mm. interior view. } 
16.— Valve B, 0.31 mm. interior view. 
17.— Valve C, 0.28 mm. exterior view, from right posterior ambulacrum, to- } Of a single pedicellaria. 
wards margin of anal plastron. Alcoholic specimen, with spines 
measuring 30 mm. long. Barbados (?) 
18.— Valve B, 0.24 mm. interior view from right posterior interambulacrum near apical system. Test 
measuring 30 mm. long. Barbados (?) 
19.— Valve C, 0.22 mm. exterior view, from left posterior interambulacrum. Alcoholic specimen 
measuring 26 mm. long. Barbados (?) 
20.— Valve C, 0.19 mm. exterior view, from left posterior interambulacrum, near apical system. Test 
measuring 26 mm. long. Barbados (?) 
Same pedicellaria. 
| Same pedicellaria. 
The enlargement of Figures 2 to 20 is the same, but is on a slightly larger scale than those of Plates 
18-20. 
