THE STARFISHES OF THE HAWAIIAN ISLANDS. 
1069 
with membrane, so that outlines of plates are wholly obscured except when in a dry state. (Com- 
pare figs, la and lb, pi. xxvi.) A definite crease or line in the membrane runs from the furrow 
obliquely outward toward the margin of body. These wrinkles separate each adambulacral plate, 
and every second or third line is confluent with the suture between 2 inferomarginals, while the 
intermediate lines end between the furrow and margin. Actinal surface of adambulacrals bears 6 to 8 
subspherical granules of unequal size, disposed in an irregular longitudinal series along the middle of 
plate. They are covered by thick membrane and are not very conspicuous until animal is dry. 
(PI. xxvi, fig. lb.) On outer half or third of ray these are replaced by a single, stout, short, taper- 
ing spine, exceeding in length the furrow spinelets, which are here quite short. A few plates bear, 
near the adoral margin, between the furrow series and granules, a single rather long 2-jawed pedicel- 
laria, about as long as the nearest furrow spinelet. Each jaw is narrow spatulate and curves slightly, 
like a pair of tongs, to meet its companion. 
Mouth plates are large and prominent actinally, with a very extensive furrow margin. Furrow 
spinelets 11, stout, the outer ones similar to the adambulacral furrow spinelets, but the 2 or 3 inner 
larger and heavier. Actinal surface is armed with prominent granules, subspherical to thimble- 
shaped, arranged in an irregular series parallel to median suture, and another continuing the linear 
series of adambulacrals. Numerous much smaller granules are scattered here and there. 
Actinal interradial areas are covered with membrane, which is lined with fine creases or wrinkles, 
as already noted. The plates are irregularly polygonal or roundish, and are arranged in chevrons, 
decreasing in size toward the margin. They bear a central group of subspherical or low thimble- 
shaped granules, the rest of exposed surface being beset with smaller, widely spaced granules. The 
series adjacent to adambulacrals usually bears 3 to 10 larger granules, the next series 3 to 6, and the 
other plates 1 or 2 such. 
Madreporic body is large, hexagonal to subcircular, situated about one-third distance from center 
to extreme margin. Its exposed surface is flat and sunken a trifle below the level of the surrounding 
membrane except in the dried state. Striations fine, radiating. 
Anal opening subcentral, surrounded by 5 plates larger than their neighbors. The aperture is 
guarded by about 8 tooth-like granules. Tube feet with large sucking disks. 
Color in life: Dorsal surface deep cadmium yellow to cadmium orange; lower surface cream color 
to cadmium. In alcohol, dull light brownish to deep brown. 
Variations: There appears to be a dimorphism in this species. Some specimens (in the majority) 
have longer, slenderer rays than others. Superficially they would be taken for a different species, 
but I am unable to find any other correlative character by which to separate them. The type 
specimen is neither the one extreme nor the other, but is rather short-rayed, however. The following 
table of measurements (in millimeters) will give an idea of the difference: 
Measurements of specimens of Antheniaster epixanthus. 
Station. 
Major 
radius. 
Minor 
radius. 
Ratio. 
Supero- 
margi- 
nals. 
Width 
of ray 
between 
second 
and third 
supero- 
margi- 
3813 
mm. 
50 
1.9- 
”l7 
™™3 
4080 (type) 
90 
47 
1.92+ 
20 
40 
411* 
40 
1.74 
15 
34 
4080 
96 
42 
2.3 
19 
35 
4080 
77 
32 
2.4 
20 
28 
4081 
90 
35 
2.57 
22 
29 
4081 
65 
24 
2.7 
18 
20 
The presence of pedicellarite on adambulacral plates is also subject to great variation. In the type 
there are only a few scattered along the base of ray, and on the largest specimen none are to be found. 
On the other hand, a medium-sized specimen of the long-rayed phase has 4 to 12 on each adambulacral 
series of disk. At first this might appear of specific value, but pedicellarise are either very few or 
absent from all the other long-rayed specimens, except one which is intermediate between the 
extremes. 
