A MONOGRAPH OF THE EXISTING CRINOIDS 245 



master); p. 13 (common to southeast Africa and Ceylon, but not found in the Arabian Sea); 

 Ann. and Mag. Nat. Hist., ser. 8, vol. 7, 1911, p. 644 (discussion; list of known species); Amer. 

 Journ. Sci., ser. 4, vol. 32 (old ser. vol. 182), No. 188, Aug. 1911, p. 129 (appears to have given 

 rise to the West Indian Comalilia, Microcomuttda, and Leptonemasler); Memoirs Australian 

 Mus., vol. 4, pt. 15, 1911, p. 725 (absent from Australia); Crinoids of the Indian Ocean, 1912, 

 p. 9 (absent from Australia); p. 10 (absent from Japan; reason); p. 11 (represented in the 

 Cej'lon region); p. 12 (represented in the southeast African region); p. 20 (bathymetric range); 

 p. 55 (in key) ; p. 77 (original reference; type) ; Internal. Revue d. gesamt. Hydrobiol. u. Hydrogr., 

 1914, pp. 3 and following (represented in the Atlantic by Leptonemasler and Comalilia; range); 

 Beitrage zur Kenntnis der Mecresfauna Westafrikas, Echin. II, Crinoidea, 1914, p. 309 (cor- 

 responds to Leptonemasler); Die Crinoiden der Antarktis, 1915, p. 181 (range; represented in 

 the Atlantic by Leptonemasler and Comalilia); American Naturalist, vol. 49, 1915, p. 525 (bathy- 

 metric range); p. 539 (asymmetrical disk); Unstalked Crinoids of the Siboga E.\ped., 1918, 

 p. 3 (in key) ; p. 19 (key to the included species) ; Journ. Washington Acad. Sci., vol. 9, No. 5, 

 1919, p. 136 (disk compared with that of Holopus). — Gisl]6n, Zool. Bidrag fr&n Uppsala, vol. 9, 

 1924, p. 97 (pinnule articulations). 



Comanthus (part) A. H. Clark, Proc. U. S. Nat. Mus., vol. 40, 1911, pp. 8, 18, 19; vol. 43, 1912, 

 p. 385. — H. L. Clark, Biol. Results Fishing E.xper. F. I. S. Endeavour, 1909-14, vol. 4, pt. 1, 

 1916, p. 17. 



Comanthus (Validia) (part) A. H. Clark, Proc. U. S. Nat. Mus., vol. 40, 1911, pp. 18, 19. 



Diagnosis. — A genus of Capillasterinae including species in which the arms are 

 10 in number; there are no prominent carinate processes on the basal segments of 

 the earlier pinnules; all the pinnules are present; the pinnules of the first 2, 3, or 4 

 pairs have terminal combs which are confined to the distal half and are composed 

 of teeth which are seldom, and never much, higher than the width of the segments 

 bearing them; none of the segments of the proximal pinnules are more than slightly 

 longer than broad; there is no modification of the dorsal surface of the lower brachials; 

 the brachials and pinnule segments have very spinous distal ends; the cirri are never 

 excessively slender; and the arms are always more than 20 mm. in length. 



Geographical range. — From the Seychelles, Amirante Islands, Red Sea, and 

 Ceylon to northern and eastern Australia and Tasmania, the Bonin Islands, southern 

 Japan, the Philippines, and Macclesfield Bank. 



Bathymetrical range. — From the shore line down to 984 meters. 



Thermal range. — From the warm surface water of tropical seas down to 13.7° C. 



Remarks. — The species of Comissia vary from rather large, with the arms 

 170 mm. long and 25-30 cirrus segments, to very small, with the arms not more than 

 30 mm. long and only 9-1 1 cirrus segments. 



Some of the species are very spiny, while others are smooth. Some have weak 

 and slender cirri with elongate segments, while in others the cirri are stout and 

 strongly recurved in the distal half. In some the arm bases are almost at right angles 

 with the dorsoventral a.xis, so that the arms lie practically in the same plane, while in 

 others the arm bases make a rather sharp angle with the dorsoventral a.xis. 



Taken as a whole Comissia is a rather heterogeneous assemblage, and some of the 

 species groups within it seem to have little in common with others beyond the posses- 

 sion of only 10 arms. 



We know so httlc about most of the included species that any more detailed 

 generalization at the present time would be premature. 



