A MONOGRAPH OF THE EXISTING CRINOIDS 



91 



under the genus, with the synonymy and ranges, C. eupedata, C. propmqua, C. vaMa 

 and C incerta, accepting Crotalometra in the sense of its formal description instead of 

 its first appearance. Under Thalassometra were listed Th. magnicirra, Th. rustica Ih 

 sentifera and Th. injelix, herein referred to Crotalometra. In a paper on the crinoids of 

 the British Museum published in 1913 there appears the heading "Genus Aglaometra 

 A H Clark" under which are given notes on Aglaometra valida and A. incerta. 



The genus Aglaometra is inserted in a key to the genera of the subfamily Thalasso- 

 metrinae in my memoir on the unstalked crinoids of the Siboga expedition, and a key to 

 the included species (vera, propinqua, sulcata, eupedata, valida, and incerta) is given. 

 These 10-armed forms are therefore definitely removed from the genus Crotalometra, 

 which in the Siboga report is given as including C.flava, C. porrecta C.sentijera, C. rus- 

 tica C. marginalia, and C. magnicirra. Since the publication of the Siboga report the 

 status of the genus Crotalometra has remained unchanged. In the present work the 

 two Atlantic species, porrecta m&flava, which differ markedly from the Indo-Pacific 

 forms, are set apart as constituting the new genus Koehlermetra. 



KEY TO THE SPECIES IN THE GENUS CROTALOMETRA 

 a> Brachials beyond the proximal third of the arms with the central portion of the distal dorsal edge 

 lanced Into Ion, overlapping spines which are more or less flattened dorsoventraUy and 

 rounded or truncate at the tip; 12-19 arms 150-16C > mm long; dm 40-50 mm long w.th ^51-62 



segments (Maldive and Laccadive Islands; 914-1,265 meters)... sentifera (p. 91) 



a* Brachials beyond the proximal third of the arms not produced into long overlapping dorsal sp nes. 



'^Bralhals beyond the proximal third of the arms strongly overlapping, the central portion of the 



" distLl dorsal edge somewhat produced and spinous; 13-20 arms 90-150 mm. long; cur, 55-85 



mm long with 45-70 segments (Moluccas and the Malay Archipelago to Formosa and Madras; 



V BraSLy^ndule" p'roximaVthird'oVthe arms" wYtnVh;" d^;rboVder;"u"nn W dified or at least 

 n t conspicuously modified; 16-20 (usually 20) arms 75-110 + mm. long; c irn 55- 70 -.long 

 with 50 63 segments (southeastern Africa from Durban to Port _E^h^91-Wl ( [?823] 

 meters) 



CROTALOMETRA SENTIFERA A. H. Clark 



Plate 32, Figures 100-103 

 , , ,v „ A H O.ark Proc Biol Soc. Washington, vol. 22, 1909, p. 147 (description; 



"ttwN^ W4W E. 03 fms.); Proo.V EL Nat. Mus., vol. 39, 1911, p. 551 

 compared with C. 1%£ Unstalked crinoids of the 5i 6 0ff a-Exped., UlJjM (m key; range; 

 feTencesV Journ. L inn. Soc. (Zool.), vol. 36, No. 249, April 1929 p. 6o4 (compared w.th C 

 ZX sp nov. [ = C. rusUca}); John Murray Exped. 1933-34, Sc. reports, voh4 No.4 1936 

 enaa neiia sp l (jtfatafctM station 158; notes; range), pp. 98, 101, 103. 



T^ZZ 3£f kS££ Crinoids of the Indian Ocean, 1912, p. 201 (synonymy; descr.p- 

 tion; locality), fig. 37, p. 202. 



Diagnostic jeatures.-The brachials of the middle and outer portions of the arms 

 have the central portion of the distal edge produced into long and conspicuous more or 

 bsIdorsoventraUy flattened overlapping spines. The 12-19 arms are 1*0-160 mm. 

 long and the cirri are 40-50 mm. long with 51-62 segments. 

 Description— The cirri are XX, 59-62, 50 mm. long. 



?hel-6 arms are from 150-160 mm. long. After the proximal third of the arm 

 the blchLls bear long overlapping spines which are more or less flattened dorsoventraUy 

 and rounded or truncated at the tip. 



