294 BULLETIN 82, UNITED STATES NATIONAL MUSEUM VOLUME 1 



ble that mawsoni will prove to be congeneric with Solanometra antarctica rather than 

 with Florometra magellanica. 



History. The first known species of this genus, Florometra magellanica, was described 

 under the comprehensive name of Antedon and was also mentioned under the generic 

 name Comatula, used as a synonym of Antedon. 



On the creation of the genus Heliometra in 1907 all the known species now referred 

 to Florometra which had then been described were transferred to it from Antedon. 



In 1911 Heliometra was restricted to include H. glacialis only, and Solanometra 

 was suggested to cover all the other species, now included in that genus and in Floro- 

 metra. This conception of Solanometra was never actually stated, though it may 

 readily be inferred from the earlier references to the name. 



The name Florometra first appeared, as a subgenus of Promachocrinus, with no 

 diagnosis, in 1913, one species, listed as Florometra magellanica, being given under it. 

 In 1914 Florometra was mentioned again as a subgenus of Pro7nachocrinus and Antedon 

 mariae was given as the type species; Antedon asperrima, A. hondoensis, A. inexpectata, 

 A. laodice, A. magellanica, A. mariae, A. perplexa, A. rathbuni, A. serratissima and A. 

 tanneri were assigned to it. In 1915 a diagnosis was published and the type species 

 was again given as A. mariae; it was regarded as a subgenus of Promachocrinus. The 

 species assigned to it in 1914 were again mentioned, this time with Florometra instead 

 of Antedon as the generic name. 



[NOTE BY A.M.C.] In recent years the working up of the many collections taken 

 in the Antarctic and Southern Ocean has produced a number of new species attributed 

 to this genus. The first of these was F. mawsoni described in 1937 by A. H. Clark 

 from the Australasian Antarctic Expedition collection. In 1938 and 1939 Dr. Dilwyn 

 John described Florometra antarctica, spinulijera and goughi from the Discovery, Banzare 

 and Scotia collections respectively. In 1939 he acknowledged antarctica as a synonym 

 of mawsoni. F. spinulijera has oral pinnules with distal segments several times longer 

 than wide quite unlike the species of this subfamily and although it is just possible 

 that this is attributable to the relatively small size of the unique type, I am transferring 

 it to the genus Tonrometra in the subfamily Bathymetrinae. A new species from later 

 Discovery collections is described here by me under the name Florometra austini. 



KEY TO THE SPECIES OF FLOROMETRA 

 [Modified by A.M.C.] 



a 1 . Third syzygy usually between brachials 16+17, sometimes 15+16. 



6 1 . Basal segments of the oral pinnules markedly carinate and appearing much broader than the 



rest of the pinnule especially in lateral view. 

 c 1 . Longest cirrus segments two and a half to three tunes as long as broad (Cape Horn north 



almost to Valparaiso, Chile; 22-594 meters) magellanica (p. 295) 



c 2 . Longest cirrus segments not more than twice as long as wide. 



d 1 . Brachials short, the longest in the proximal part of the arm being distinctly broader than 



long (Lower California to the Alaska peninsula; 11-1252 meters) _. serratissima (p. 299) 



d 2 . Brachinls longer, the longest being about as broad as long (southeastern and southern 



Japan; 128-1073 meters) mariae (p. 309) 



V. No carinate process on the proximal segments of the oral pinnules (Panama Bay northward 



to the Tres Marias Islands; 523-1429 meters) tanneri (p. 313) 



a 2 . Third syzygy usually between brachials 14+15. 



6'. Third syzygy as often between brachials 16+ 17 or 15+16 as 14+ 15, even in the Bame specimen; 

 cirri XXX-L (southeastern and southern Japan; 128-1073 meters) mariae (p. 309) 



