Zoology.-] NATURAL HISTORY OF VICTORIA. \_EcUnodermata. 



Plate 200, Fig. 1. 



xlSTERINA CALCAR (Lam. restricted by Gray). 

 The Eight-rayed Cushion Starfish. 



[Genus ASTERINA (Nardo). (Sub-kingdom Radiata. Class Echinodermata. Order 

 Asteroidea. Family Asterinidae. Sub-family Asterininse.) 



Gen. Char. — Body tumid, with five to eight short blunt rays, back convex ; oral surface 

 flat or concave. Ossicula of each surface with one or more mobile tapering spines ; edge sliarp, 

 with very minute marginal plates. Each of the ossicula of upper surface cresent-shaped, with 

 a marginal series of very short spines ; ambulacral spines in groups of two or five.] 



Description. — Very gibbous, with eight short, nearly parallel-sided rays 

 abruptly bluntly rounded at the tip; taking- centre of mouth to tip of rays as 100, 

 to middle of intervening margin, /A^. Adambulacral plates bordering ambulacral, 

 each with two spines. Interambulacral plates between ambulacra on lower or oral 

 side, each forming a broad slightly radiated base to a large, tapering, single spine. 

 Plates of upper or dorsal surface thick, crescent-shaped, with from six to twenty 

 minute spines fringing the convex edge of each in one or more rows. There are six 

 long, slender, tapering spines to each of the large, interambulacral, trigonal oral 

 plates, forming groups round the mouth ; the middle pair longest, the others 

 gradually diminishing to outer ones. Madreporiform tubercle subtrigonal. Colour: 

 Very irregularly varied in different individuals, with usually the rays dull purple, 

 mottled with darker, and more or less of dull red towards maigin between the rays ; 

 others have these positions of the red and purple reversed ; others are uniform rich 

 purple above. Underside pale flesh-colour, with occasional pale purplish portions. 

 Jlleasurements: Diameter of ordinary specimen from tip to tip of rays, 3 in. 6 lines; 

 irom edge to opposite edge between rays, 1 in. 6 lines ; depth, 6 lines. 



•Reference. — ^ Asierias calcar, var. G. octogona, Lam. Anim. sans vert., 

 V. 2, p. 557. 



This is the commonest of all the Starfishes on the coast ; 

 adhering to stones below low-water mark. It is extremely 

 variable in the extent and intensity of the purple on upper 

 surface. The whitish central patch in the specimen figured is 

 very unusual. It is easily distinguished from the almost equally 

 common A. Gunni^ by having eight longer and more parallel- 

 sided rays, and by having a single spine on each of the inter- 

 ambulacral plates between the ambulacra below. 



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