750 



706 " THETIS " SCIENTIFIC RESULTS. 



COM ASTER MULTIFIDA (J^, MiUier). 



Comatula multiradiata (part) (nob of Linnaeus), 1816, Lamarck, 



Hist, nat des aniinaux sans vertebres, vol. 2, p. 533. 

 Alecto mnltifida, 1841, J. Miiller, Arcliiv. fiir Naturgesch, 1841, 



i., p. 147 (based on preceding). 

 Actinotnetra inuUijida, 1884, Bell, Rep. Zool. Coll. H.M.S. 



"Alert," p. 169 [Percy hland ; Albany Island ; Prince of 



Wales Gliannel) ; 1888, P. H. Carpenter, " Challenger " 



Repoi-ts, Zool., vol. 29, p. 383 {Qiieendand ; Torres titrail) ; 



1894, Bell, Proc. Zool. Soc, 1894. p. 394 {N.W. Australia). 

 Actinotnetra variabilis (part), 1884, Bell, Rep. Zool. Coll. H.M.S. 



"Alert," p. 169 (l)ut not reference to plate). [Thursday 



Island). 

 Actinometra belli, 1898, Diiderlin, Denk. Ges. Jena, vol. viii., 



p. 479 (i)art), plate, tig. 4 (but not 4a). 

 Comaster caiyenteri, 1908, A. H. Clark, Proc. U. S. Nat. Mus., 



vol. 33, p. 686. 

 Differential Characters. — Comaster multijida usually has about 

 forty arms, the IE Br series l)eing4(3 + 4) and the [II Br series 2. 

 This arm structure, combined with the characteristic cirri and 

 the occurrence of terminal combs at intervals on the outer 

 j)innules to the arm tips, make the species an easy one to 

 recognise. 



Australian Records. — This species has been reported from 

 North-western Australia, and from Percy and Albany L-slands, 

 and Prince of Wales Channel. 



Distribution. — This form ranges from Northern Australia 

 northward to the Moluccas. 



Professor Doderlein in his paper upon a collection of Coma- 

 tulids from Amboina and Thursday Island has confused this 

 species with Comantheria belli; in his figures, supposedly of that 

 species, tig. 4 obviously represents Comaster multijida ; this 

 explains why it has not developed the characteristic carinatiou 

 of the pinnule segments. 



In the type of Alecto multijida, which I examined while at 

 Paris, there are forty-five arms ; the typical scheme of arm 

 division is as follows : —There are two IIBr 4 (3 + 4) series; each 

 of these gives off one III Br 2 series externally; the latter bear 

 outwardly an undivided arm, and inwardly a IV Br 2 series. 

 The elements of the III Br series are united apparently by a 

 close synarthry which has not become metamorphosed into a 

 pseudosyzygy as is the case in Comaster typica. This is probably 

 what misled Carpenter and caused him to place this species in 

 the " Parvicirra group " instead of next to its closest relative, 

 C. typica. 



