ASTEROIDEA 155 



St. WS 824. Falkland Islands 52° 29I' S, 58° 27J' W, 146-137 m., 4 specimens. 



St. WS 825. Falkland Islands, 50° 50' S, 57° 15^' W, 135-144 m., i specimen. 



St. 1563. Marion Island, 48° 48-4' S, 37° 49-2' E, 101-106 m., 2 specimens (intermediate). 



St. 1564. Marion Island, 46° 36-5' S, 38° 02-3' E, 108-113 m., 4 specimens. 



Although it has long been customary to regard Porania of the Magellanic region as 

 identical with that of Kerguelen, Crozet, and Prince Edward Islands, the case is far 

 from being established. The only continuity of distribution may well be through the 

 really Antarctic glabra which is probably the parent form of both stocks — that of the 

 American Quadrant and that of the African Quadrant. Be that as it may, P. antarctica 

 does not range as far south as the Antarctic Convergence except at Kerguelen. 



The specimens from St. 1564, Marion Island, slightly north of the Antarctic Con- 

 vergence, are typical antarctica and have longer subambulacral spines and less robust 

 abactinal spines than specimens from the Falkland region. The two examples from St. 

 1563 have only a few abactinal spines in the radial areas and are intermediate with 

 glabra. Three specimens from St. 1562, Marion Island, are also intermediate but 

 nearer to glabra (q-v.). 



I believe a good series of specimens from the African Quadrant north of the Antarctic 

 Convergence would be demonstrably different from the South American form. The few 

 specimens obtained by the ' Discovery ' from Marion Island substantiate this conclusion. 



The Falkland specimens vary considerably in the number of abactinal spines, some 

 having more numerous and larger spines than Sladen's fig. 5 which represents about the 

 minimum number for adults. Small examples have the fewest spines — sometimes only 

 3 or 4 along the radial line. 



In glabra the young may have small tubercular spines but these disappear in the 

 adult, whereas in antarctica the number and size increase with age. 



A specimen from St. WS 80, with R 60 mm., r 32 mm., has 30-35 stout tubercular 

 spines to each ray, not counting a pentagon of 11 in centre of disk. It resembles, 

 dorsally, an arcuate pentagonal Echinasterid such as Poraniopsis. 



Apparently the dermal spinelets oi glabra do not occur in this race except as rudiments 

 in young specimens. 



Colour note, St. WS 245 : abactinal surface brilliant deep scarlet. 



Type locality. Kerguelen. 



Distribution. Prince Edward, Marion, Crozet Islands; Kerguelen; Falkland- 

 Magellan Plateau, north along the Chilean coast to Calbuco (41° 45' S). 



Porania antarctica glabra Sladen 



Porania glaber Sladen, 1889, p. 360, pi. 59, figs, i, 2. 



Porania spiciilata Sladen, 1889, p. 362, pi. 59, fig. 4. 



Porania antarctica Studer, Die Seesterne Sud-Georgiens, Jalirl). wiss. Anstalten zu Hamburg, 1885, 



p. 160.— Ludwig, 1903, p. 22, pi. 2, figs. 18-20. — Koehler, 1906, p. 10.-1911, p. 27.-1912, p. 



66.— 1917, p. 42.— 1920, p. 178, pi. 33, figs. 6, 7.— 1923, pars, p. 74 (Graham Land, South 



Georgia). 

 Porania armata Koehler, 1917, p. 43, pi. 7, figs. 3, 4, 7, 12.— Doderlein, 1928, p. 297. 



