ASTEROIDEA i99 



Subgenus Apterodon 



Pteraster stellifer Sladen 



Pteraster stellifer Sladen, J. Linn. Soc. Land. (ZooL), xvi, p. 193.— 1889, p. 474, pi. 74, figs, i, 2; 



pi. 77, figs. I, 2. — Bernasconi, 1937, p. 176. 

 Pteraster hunteri Koehler, 1920, p. 165, pi. 37, figs. 4-10; pi. 38, fig. 8; pi. 75, fig. 8.— 1923, p. 81.— 

 Bernasconi, 1937, p. 176. 



St. 175. Bransfield Strait, South Shetlands, 200 m., i specimen. 



St. 652. Burdwood Bank, 169-171 m., 2 specimens. 



St. WS 81. 8 miles north-west of North Island, West Falkland Islands, 81-82 m., sand, 3 speci- 

 mens. 



St. WS 85. Falkland Islands, 52° 09' S, 58° 14' W, 79 m., sand and shells, 5 specimens. 



St. WS 88. Falkland Islands, 54° S, 64° 57' 30" W, 96-127 m., shell and stones, i specimen. 



St. WS 216. Falkland Plateau, 47° 37' S, 60° 50' W, 219-133 m., fine sand, 2 specimens. 



St. WS 224. Falkland Plateau, 50° 18' S, 65° 07' W, 124-126 m., i specimen. 



St. WS 228. Falkland Plateau, 50° 50' S, 56° 58' W, 229-236 m., 23 young. 



St. WS 231. Falkland Plateau, 50° 10' S, 58° 42' W, 167-159 m., fine green sand, 2 young. 



St. WS 237. Falkland Plateau, 46° S, 60° 05' W, 150-256 m., coarse brown sand and shells, 48 

 young. 



St. WS 243. North-east of Falkland Islands, 51° 06' S, 64° 30' W, 144-141 m-, coarse dark sand, 



I young. 



St. WS246. Falkland Islands, 52° 25' S, 61° W, 267-208 m., coarse green sand and pebbles, 



I young. 

 St. WS 248. Falkland Islands, 52° 40' S, 58° 30' W, 210-242 m., fine green sand, pebbles, shells, 



I specimen. 



St. WS 781. Falkland Islands, 50° 30' S, 58° 50' W, 148 m., i specimen. 



St. WS 795. East of Cape Tres Puntas, 46° 14' S, 60° 24' W, 157-161 m., i specimen. 



St. WS 800. 48° 15' 45" S, 62° 09' 52" W, 137-139 m., I specimen. 



St. WS 824. Falkland Islands, 52° 29I' S, 58° 27!' W, 146-137 m., 13 specimens. 



St. WS 831. 50° 50' 30" S, 66'' 10' 30" W, 98-102 m., 2 young. 



St. WS 871. 53° 16' S, 64° 12' W, 336-341 m., 2 young. 



The largest specimen (St. WS 85) measures R 23 mm., r 13 mm., and is therefore 

 smaller than the type, in which these dimensions are respectively 34 and 23 mm. 

 Sladen's figures show the general habit satisfactorily, although in this series of speci- 

 mens the stellate protuberances of the supradorsal membrane are seldom so prominent 

 as shown by Sladen, and are masked altogether in a very considerable proportion of the 

 specimens. The condition pictured by Sladen is approached closely by the series from 

 St. WS 824. Here the 6-8 peripheral paxillar spines radiate more or less symmetrically 

 from the pedicel top, and there is usually a single central spine. A feature character- 

 istic of most specimens is the conspicuous lateral fringe of actinolateral spines, and the 

 deeply emarginated web of their membrane. While in some specimens this from above 

 defines the entire ambitus, in others from the same station it is visible only on outer part 

 of ray. It is not indicated in Sladen's pi. 74, fig. i. 



The figures of the actinal surface given by Sladen are good, although the form of the 

 adambulacral comb must not be interpreted too literally as it varies even in the same 

 specimen. If the membrane is greatly contracted the adambulacral spines seem to 



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