ECHINODKRMS FROM WEST AUSTRALIA. 243: 
chief points of distinction are the wider and terminally rounded rays^ 
the thick skin which conceals the skeletal plates and is not at all smooth and 
shiny when dry (the feature from which P. vernicina gets its appropriate- 
name), and the absence of tubercles, spinelets, or even granules on the distal 
marginal plates, in P. obesa. The West Australian species seoms to be 
somewhat larger than the one from the east coast, the largest specimens of 
which have R = 50-60 mm. 
ASTEKINA BUETONII. 
Gray, 1840, Ann. Mag. Nat. Hist. vi. p. 289. 
There are half a dozen very typical specimens of this little sea-star, ona 
dredged off Long Island and the other from Wooded Island. The largest 
has 11 = 26 mm. None of the specimens has retained any of its natural 
colour. The discovery of this species at the Abrolhos extends its known 
range very far to the south on the Australian coast. 
ASTBBINA GUNNII. 
Gray, 1840, Ann. Mag. Nat. Hist. vi. p. 289. 
There is a badly damaged small specimen (R=27 mm.) of this southern 
species in the collection, but it is not from the Abrolhos. It was dredged off 
Garden Island near' Fi-emantle, which is probably about the northern limit 
of the species on the western coast. 
Parastbrina crassa Fisher. (PI. 13. figs. 3, 4.) 
Patina (?) crassa Graj', 1847, Proc. Zool. Soc. London, p. 83. 
Parasterina crassa Fisher, 1908, Smithson. Misc. Coll. lii. p. 90. 
A sea-star dredged off Fremantle is apparently to be referred to this- 
species, as it answers well to Perrier's (1875, Arch. Zool. Exp. v. p. 142) 
rather detailed description except for its much larger size. Grray makes no 
reference to the size of his specimen, but Perrier says "■ d=10 mm.'" From 
the context one would infer that d meant the distance from tip to tip of 
alternate rays — that is, the diameter of the entire animal ; but in that case the 
specimens in the British Museum are tiny indeed, and it seems incredible 
that the description given could apply to so small an individual. If d refers to 
the diameter of the disk, then Perrier's specimen was only about half as large 
as the one in hand. Possibly the 10 is a misprint for 100, but in that case- 
the present specimen is much smaller than those in the British Museum. 
Perrier refers several times to resemblances to Pentanogaster. These led me 
for a time to feel sure that my specimen could not be". P. crassa, as I see 
nothing in which it is the least like Pentagonaster, save possibly the adam- 
hulacral armature, where a slight resemblance might be imagined. 
. .The present specimen has R = 36 mm. and r = 9, and R is therefore equal 
to 4r ; Perrier says R = 3f r, a difference easily understood if his specimen 
had r only 5 mm. Pei-rier says that the largo ossicles in the dorsal skeleton 
