THE STARFISHES OF THE HAWAIIAN ISLANDS. 
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group. In a series below these, extending to the lower (inner) end of plate, are from 7 to 11 spines 
and spinules similar to the 2 just described except in size. Of these the 2 or 3 following the lateral 
spines are short, and then come 5 conspicuous, slender, tapering, sharp-pointed spines, increasing in 
length toward the innermost, which is about 5 mm. long, and is situated at the inner end of plate. 
Between any two of them there is usually a short spinule, about one-fourth to one-third their length. 
Occasionally there is an odd spine, set out of line with the above series, toward the median line of the 
plate. (2) The second series of spines forms a semicircular row about the adoral side of the large flat 
spine, and the lower (inner) end of the series abuts against the regular aboral series, just below the 2 
slender marginal spines which accompany the big one. Two spines of this series are placed in an 
oblique row between the flat spine and the superomarginal plates. Immediately adoral to the large 
spine are 1 or 2 short spinules, and then between these and the regular aboral series 5 to 7 slender, very 
sharp, tapering spines, forming a graduated series which merges into the regular transverse series as 
described above. All are closely appressed to the base of the flat spine. The abactinal surface of each 
inferomarginal is covered with papilliform spinelets similar to those investing the superomarginals, 
while the actinal surface is crowded with stouter, clavate, papilliform spinelets, each sheathed with a 
thick, pulpy investment. They become slightly larger toward the lower end of the plate. 
Adambulacral plates numerous, separated by wide sutures and with an angular margin to furrow. 
Armature composed as follows: (1) A furrow series of 3 long, slightly tapering, round-tipped or 
truncate-spines, the median of which is longest and stoutest; all are compressed, especially the median, 
which is saber-like; on the basal portion of the ray usually stand 2 of the actinal spines, one at either 
end of the furrow series, these, however, shorter and placed behind the lateral furrow spines. 
(2) Spines of the actinal surface of plate in 3 irregular longitudinal rows of 3 (or 2) each. The median 
spine of each series is usually flattened and roundly truncate at the tip, the 2 laterals tapering and 
much smaller. Behind the 3 series of actinal spines are 3 to 6 smaller spinules or spinelets, irregularly 
placed, on the outer end of the plate. The actinal spines, especially the smaller, are invested with 
a sheath of pulpy membrane, which greatly increases their thickness. On a dried specimen these 
same spines are slender, cylindrical or slightly compressed, and exceedingly fragile. 
Actinal intermediate plates, few in number (8 to 10), are very small and confined to the incon- 
spicuous interradial area, which does not extend beyond first inferomarginal. The interradial area 
forms a triangle the sides of which do not exceed 5 mm. The plates are covered with spinelets similar 
to those of the. inferomarginals. 
Mouth plates are narrow and not prominent actinally. Armature consists of a marginal series 
of stout, flattened, blunt spines, 4 of which are arranged in a graduated series on the inner end of the 
plate, the 2 nearest median suture being largest, and the combined series of the 2 companion plates 
form a horizontal fan-shaped series. The marginal series, reduced ■ in size, is continued for a short 
distance along the edge of the plate adjacent to first adambulacral. On actinal surface a superficial 
series of blunt or pointed, flattened spines extends from end to end of plate along the median sutural 
margin. Between this and marginal series is an intermediate row of 8 or 10 spines which extend about 
two-thirds the distance to outer end of plate and are graduated in length, the longest being innermost. 
Madreporic body of medium size, situated nearly midway between the margin and center of disk. 
Striations not conspicuous. 
Color in life from immature specimens: Abactinal paxillar area deep vinaceous cinnamon (except 
paxillfe crowns, which are lighter pinkish buff) , shading to cinnamon at tips of arms. Marginal plates 
buff; large flat marginal spines rose pink. Actinal surface whitish. Color in alcohol dull light brown. 
Variations: The chief variations in this species are in minor details of spinulation of the actinal 
surface of inferomarginals and the relative length of the arms. All the arms of a single specimen 
are not always exactly the same length. If the minor radius be taken as a unit, the rays of the type 
are 9.5, 9.3, 9.2. Another specimen of about the same size varies as 8.25, 9.5, 9.3, 8.1, 9.5. The average 
length is always well above 9:1, while one example has an arm as long as 10:1. The armature of the 
inferomarginal plates is, as a rule, more robust toward the base of the ray, particularly in respect to the 
actinal series of spines. In some specimens the spines on the basal plates are subequal in length, 
there being, instead of 5 large spines with small intermediate spinelets, about 7 or 8. Usually, how- 
ever, the formula already described holds true. 
Young: A single half-grown individual (E=85 mm.; r=10 mm.) differs from the fully adult in 
having slightly shorter arms and more prominent spinules on superomarginals, there being one on 
