42 ‘* PNDEAVOUR’” SCIENTIFIC RESULTS. 
Superomarginal plates nearly or quite vertical in position, 
and hence scarcely to be seen from above, 30-32 in number, 
the interradial ones much higher than long, covered with 
granules similar to those on the abactinal plates ; there are 
about 200 granules on one of the big interradial supero- 
marginals. Terminal plate small, nearly circular, consider- 
ably swollen. Inferomarginals very similar to supero- 
marginals in number, position, size and form ; they have the 
same granular covering. In the holotype and in some other 
specimens intermarginal plates of irregular size, shape and 
position occur in considerable numbers, but this is not a 
constant feature, since in some individuals such plates appear 
to be rare if not altogether wanting. Actinolateral plates in 
about 7 series ; the first, adjoining the adambulacrals, extends 
nearly or quite to the arm-tip, the second goes about the 
three-fourths of the way, and the third more than half; all 
the actinolateral plates are covered by granules distinctly 
coarser than those on the abactinal surface. 
Adambulacral plates about 60, longer than wide, with a 
fairly straight margin; on this margin is a series of 4 sub- 
equal, squarish, blunt spines, about 2 mm. long (occasionally 
a fifth, adoral, much smaller spine occurs); outside this: 
series is a second, consisting of 3 or 4 shorter, but thicker 
spines, and external to these is a series of 4 much smaller 
Fig. 4.x10. 
spines or angular granules, which do not much exceed the 
granules on the actinal plates. Oral plates not conspicuous. 
or peculiar ; even the oral spines are not strikingly larger 
than those on the adjoining adambulacrals. No pedicel- 
larie were detected anywhere. 
