A. H. CLARK : THE CRINOIDS OF THE INDIAN OCEAN. 161 



'f. India. — One specimen. 



Other Records.— Fadiffolu, Muhlos, :Malclives ; :\Iuhlos, Maldives. 



DECAMETRA ARABICA sp. nov. 



Antedon carinata Brit. Mus., MS. 



Description.— Cirri XIX. 26-27, 13 mm. long, slender, the earlier segments 

 about twice as broad as long, the terminal about as long as broad ; small paired 

 dorsal spines are developed from the ninth or tenth segment onward. 

 ■ The ten arms are 110 mm. long, resembling those of D. taprobanes. 



P absent; P, very small and weak, 4-5 mm. long; P.^ 9 mm. long with 

 fifteen segments, most of which are twice as long as broad, with produced and 

 spinous distal angles, suggesting the condition found in Oligometra serripimia ; the 

 pinnule is comparatively slender, though stiff, and tapers evenly to the tip ; P 

 is similar, but shorter, 6 mm. to 7 mm. long ; P^ is 4-5 mm. long; Pj is similar, 

 but shorter : the following pinnules are small and weak ; the distal pinnules are 

 n'5 ram. long. 



The colour in spirits is yellow, narrowly but frequently banded with purple, 

 the cirri purplish; or, blotched purple and yellow. 



Habitat. ^Muscat; 1 have examined sixteen specimens of this species in 

 the British Museum. 



DECAMETRA ALAUD^. 



Decametra alaudcp 1911. A. H. Clark, Proc. U.S. Nat. Mus., vol. 40, p. 33. 

 Habitat. — Cargados Carajos. 

 Depth. — 30 fathoms. 



DECAMETRA MOLLIS. 



Ci/llowetrn mollis 1909. A. H. Clark, Proc. Biol. Soc. Washington, vol. 22, ]i 7(i. 



Description.— Centrodorsal discoidal, thin, the polar area flat, 2 mm. in 

 diameter ; cirrus sockets arranged in one and a more or less partial second crowded 

 marginal row. 



Cirri XX, 20-22, 10 mm. long; first segment short, second and third about 

 twice as broad as long, the remainder very slightly broader than long, becoming 

 almost squarish in the terminal five or six ; second and following segments with 

 the distal dorsal edge produced and finely spinous, this projection progressively 

 narrowing distally, at the same time very slowly moving to a more proximal 

 position, after about the eighth becoming a pair of small subterminal tubercles, 

 which on the last five to seven segments give place to small median tubercles : 

 opposing spine much larger than the spines on the preceding segments, triangular, 

 the apex terminal to nearly median, in height reaching to one half or rather moie 

 of the diameter of the penultimate segment ; terminal claw very slightly longer 

 than the penultimate segment, moderately stout and moderately curved basally, 

 becoming more slender and less curved distally. 



