RECORDS OF W.A. MUSEUM. 
[147 
LINCKIA TYLOPLAX, 1 sp. nov. 
Plate XX. 
Rays 5, R. = 150 mm. r. 25 mm. R. = 6r. Br. at base= 27 
mm. Br. at half-way point = 18 mm. Disk small, but much 
elevated vertical diametre about 20 mm. Rays tapering to a blunt 
point. Whole body surface covered by a granular membrane; 
granules largest near the centres of abactinal plates smallest on 
papular areas. Abactinal skeleton composed of 3-5 irregular series 
of rounded plates, with smaller plates scattered among them. 
Larger plates, nearly all swollen into rounded or flat-topped knobs, 
2-5 mm. in diameter and about 2 mm. high. Between the plates 
are papular areas, 2-3 mm. across, with numerous small papulae. 
Madreporic body large, 7 mm. in diameter, about 15 mm. from 
centre of disk. Marginal plates fairly distinct, especially near tip of 
ray. Superomarginals about 43 on each side of a ray, the basal 
ones at least, knobbed. Inferomarginals of about the same number 
but less distinctly knobbed. Intramarginal papular areas well 
developed, nearly to tip of ray. Two series of actinal intermediate 
plates extend nearly or quite to tip of ray ; actinolateral series 
adjoining adambulacral plates much larger than the second series, 
except near tip of arm. Papular areas present on actinal surface 
not only between inferomarginals and actinal intermediate' plates 
but also between the two series of the latter, even on the actinal 
interradial areas. 
Adambulacral plates small ; armature characteristically 
Linckian ; each plate bears two short, thick, blunt spines on its 
furrow margin and a larger tubercle-like spine, 2 mm. long by 1 
mm. thick, on its actinal surface. Armature of oral plates similar 
and equal to that of two adambulacrals. No pedicellariae. 
Colour, light brown above, darkest on knobs ; actinal surface 
nearly white. 
Between Fremantle and Geraldton, W.A., 807120 fms. 
Two specimens. No. 4931. The larger specimen is the Type. 
The presence of actinal papulae would almost warrant a new 
genus for this interesting starfish. Its abactinal aspect is much 
like some species of Nardoa, but the adambulacral armature pre- 
cludes its inclusion in that genus. It does not seem to be very 
nearly related to any other previously known member of the family. 
1 Gk. tuilos — a knob ; plax — a plate. 
