258 



Thaumatometra septenirionalis \. II. Clark. 



A. II. Clark. Die Crinoidcn der Antarktis, 1915, p. [47 "unbenannte Art vom Gebiet süd- 

 westlich \ on Island" . 



1 lescription in press. 



Thaumatometra plana (A. 11. Clark . 



A. 11. CLARK. Crinoids of the [ndian Ocean, 1912, p. chometra plana). 



Orthometra A. II. l 

 The only species in the genus Orthometra is 

 1. Orthometra hibernica i.\. II. Clark). 



A. 11. CLARK. Fisheries, [reland, Sci. Invest., 1912, X" 4, p. 2 [Trichometra hibern 



Tonrometra A. H. Clark. 

 Key ti) the Species of the Genus Tonrometra. 



a None of the cirrus segments longer than the diameter of the much expanded 

 distal ends; arms 10 mm. long ; cirri XXX, t8- 20. 4 mm. long least of H a 1- 

 m ah era iGiloloj; 1089 Metres) brevipes 



a Longest proximal cirrus segments longer than the diameter of the much expanded 

 distal ends : arms probably about 40 mm. long; cirri XX — XXX, nearly 20 



n Marion Island and the Crozets; 2880 Metres) remota 



1. Tonrometra brevipes \. 11. Clark). 



A. II. CLARK. Notes from the Leyden Museum, vol. 34, [912, p. [47 {Trichometra brevipes). 



Stat. 150. o°o6' N., 129 7'. 2 E. Halmahera Sea. [089 .Metres. 1 Ex. 



The centrodorsal is low conical, twice as broad basally as high, bearing about thirty 

 |y crowded and irregularly placed cirrus sockets which have very prominent rims. 



i In cirri are about XXX, iS 2'». about 4 mm. long; the first segment is very short, 

 the second is about as long as the median diameter, the third-fifth or -sixth are the longest, 

 about as long as the diameter of the expanded distal ends; the following gradually decrease 

 in length s'o that the outermosl nine .or ten are slightly broader than long-, the longer earlier 

 segments are constricted centrally with greatl) expanded and overlapping distal ends, this 

 rapidly decreasing as the segments become shorter; the short outer segments are sub- 

 te dorsally, and bear a slight dorsal spine. 

 The radials are concealed l>y the centrodorsal. 



The llir, are extremely short, and are in close lateral apposition; the lateral edges are 

 tij everted. 



