100 NATUEAL HISTORY BULLETIN 



Oreaster reticulatus (L.) M. and Trosch. 



Asterias reticulata (pars) Linn., Syst. Nat., ed. x, p. 661, 1758. Eetzius, 

 op. cit., 1783; Diss., p. 14, 1805. Lamarck, Ann. sans Yert., vol. ii, p. 

 556, 1816. 



Oreaster reticulatus M. and Trosch., Syst. Aster., p. 45, pi. iii, fig. 2, 1842. 



Pentaceros reticulatus with P. grandis and P. gibhus Gray, Ann. and Mag., 

 vol. vi, p. 277, 1840, and Synopsis, p. 6, 1866. 



Pentaceros reticulatus A. Agassiz, North Amer. Starfishes, p. 108, pi. xvi, 

 figs. 1 to 7 (details of structure), 1877. Viguier, Nouv. Arch. Zodl. 

 Exper. et Gen., vol. vii, p. 193, pi. xi, figs. 4-6; pi. xii, figs. 3, 4 (struc- 

 ture), 1878. Nutting, Narrative Bahama Exp., pp. 52, 187, 2-02, 212 

 (colors). 



Asterias gigas Linn., Mus. Tessinianum, p. 114, pi. ix, 1753. 



Oreaster gigas Liitken, op. cit., p. 64, 1859. Yerrill, op. cit., i, p. 367, 1867. 



E. Rathbun, op. cit., p. 149, 1879. 

 0. lepidosus Grube and 0. tuberosus Behm are additional synonyms (t. 



Liitken). Also A. sebce Blainville. 0. aculeatus Gray is the young 



(t. Perrier). 



A very large massive species, having a broad, thick or high 

 swollen disk, usually with interradial contractions, in dry speci- 

 mens, corresponding to the attachment of the stout calcareous, 

 internal, interradial septa. 



Radii of a fair-sized specimen are 90°^ and 200°^°^ ; ratio, 1 :2.22. 

 Much larger specimens occur, up to 500°"°^ or more in diameter. 

 Many have shorter rays. 



The dorsal plates have a very distinctly stellate-reticulate ar- 

 rangement. The median radial row is distinct. Their portions 

 imperfectly \dsible at the surface are narrow and at their 

 nodes there is nearly always a short, stout, conical spine, both 

 on the rays and disk. The median radial ones are a little larger. 

 The whole surface, between the spines, is closely covered with 

 small unequal granules mingled with small bivalve pedicellarias 

 of similar size. The granules also extend up on the bases of the 

 spines, ending in a definite ring or border of short, angular, 

 flat or truncate granules. All the granules are minutely rough- 

 ened. 



The papular areas are very large, with great numbers of single 

 papula. 



The upper marginal plates are not large ; about 20 to 22 occur 

 on each side of each ray, in mature specimens. They form the 

 margin of the disk, but their outlines are obscured by the thick 



