A. H. CLARK : THE CRICOIDS OF THE INDIAN OCEAN. 127 



first six segments are carinate like tliose of the preceding pinnules ; Pj similar, 

 5'5 mm. or 5 mm. long ; P, and the following pinnules 6 mm. long with seven- 

 teen segments, at first twice as broad as long, becoming squarish about the eighth 

 and twice as long as broad terminally ; the pinnules are about as stout basally 

 as the two preceding, tapering rapidly in the proximal half and becoming very 

 slender distally ; the carination of the proximal segments is slightly marked on 

 the firsi four ; this carination later becomes restricted to the second and third 

 segment only, and disappears entirely in the outer half of the arm. 



The colour in spirits is violet, darker at the articulations ; the centro- 

 dorsal and the cirri are bright yellow ; sometimes the animal is entirely a light 

 yellow brown. 



Locality. — Pedro Shoal (ofl the west coast of India). — Nine specimens. 



HETEROMETRA AFFINIS. 



Antedon affinis 1890. Habtlaub, Nachr. Ges. Gottingen, Mai 1890, p. 184. — 

 1891. Nova Acta Acad. German., vol. 58, No. 1, p. 25, pi. v, figs. 18. 24. 



Heterometra affinis 1909. A. H. Clark, Proc. Biol. Soc. Washington, vol. 22, 

 p. 11. 

 Habitat. — Amboina. 



HETEROMETRA BROCKII. 



Antedon brockii 1890. Habtlaub, Nachr. Ges. Gottingen, Mai 1890, p. 183.— 



1891. Nova Acta Acad. German., vol. 58, No. 1, p. 23, pi. i, figs. 12, 13 ; 



pi. 11, fig. 17. 

 Heterometra brockii 1909. A. H. Clark, Proc. Biol. Soc. Washington, vol. 22, 



p. 11. 



Habitat. — Amboina. 



HETEROMETRA MARTENSI. 



Antedon martensi 1890. Habtlaub, Nachr. Ges. Gottingen. Mai 1890, p. 182.— 



1891. Nova Acta Acad. German., vol. 58, No. 1, p. 21, pi. i, figs. 3, «. 

 Heterometra martensi 1909. A. H. Clabk, Vidensk. Medd. fra den naturhist. 



Forening i Kobenhavn, 1909, p. 164. 



Habitat.— Singapore. 



HETEROMETRA JOUBINI. 

 Hetercmetra joubini 1911. A. H. Clabk, Proc. U. S. Nat. Mus., vol. 40, p. 25. 



Habitat. — Zanzibar. 



HETEROMETRA GRAVIERI. 

 Heterometra gravieri 1911. A. H. Clark, Proc. U.S. Nat. Mus., vol. 40, 



p. 25. 



Habitat. — Zanzib ar . 



