RECORDS OF IV. A. MUSEUM. 
116] 
DESCRIPTION OF SPECIES COLLECTED. 
Fam. : Comasteridae, A. H. Clark. 
Sub-fam.: Capillasterinae, A. H. Clark. 
Genus: Capillaster, A. H. Clark. 
CAPILLASTER SENTOSA, P. H. Carpenter. 
ComatuJa multiradiata (part) 1816. Lamarck, Hist. nat. des animaux sans vertebres, 
VOl. 2 , p. 533. 
Comatula (Alecto) multiradiata (part) 1849. J. Muller, Abhandl. d.k. preuss. 
Akad. d. Wiss. (1S47), p. 261. 
Actinometra sentosa, 1888. P. H. Carpenter, Challenger Reports, vol. 26, Zoology, 
p. 325, pi. lxvi., figs. 4-6. 
Capillaster sentosa, 1912. A. H. Clark, The Crinoids of the Indian Ocean, p. 73. 
Differential Characters. Capillaster sentosa has the same 
curious arm structure as C. multiradiata ; the IIBr series (the 
series following the first or “ radial ” axillary) are 4 (3 + 4), and all 
the succeeding division series are 3 (2 + 3) ; the first brachial of the 
free undivided arms, and the first ossicles following all the 
axillaries except the first (IBr or “radial” axillary), bear pinnules. 
It differs from C. multiradiata in possessing a much larger 
centrodorsal, which bears longer and stouter cirri, with between 
30 and 40 (commonly about 35) segments, and much more 
numerous arms, these ranging from thirty to about eighty (most 
commonly between forty and sixty-five in number. 
Locality. Between Fremantle and Geraldton. 
Material. Two specimens; one of these is small, but typical, 
with seventy-three arms ; one of the IIBr series is 2, and the remain- 
ing nine are 4 (3 + 4) ; the following series are all 3 (2 + 3) ; the 
other has thirty-three arms 115 mm. long. ; there are nine IIBr series, 
all 4 (3 +4), and thirteen IIIBr series, all 3 (2 + 3) ; the centrodorsal 
is typically large and hemispherical ; the cirri are 27 mm. to 30 mm. 
long, and are composed of 28-30 segments. 
Distribution. Capillaster sentosa ranges from the Maidive 
Islands eastward as far as the Philippines and the Moluccas, and 
southward to south-western Australia. 
Remarks. This is the first record for this species in Australia, 
though its occurrence there was to have been expected. 
