ASTEROIDEA OF NORTH PACIFIC AND ADJACENT WATERS — FISHER 119 



adradial meshes may correspond to three adjacent spaces next to the marginal 

 plates. (PI. 56, fig. 1.) 



In Sclerasterias the ray is pentagonal in specimens that have not been distorted 

 by drying or the amenities of preservation, whilo in Astrometis the ray is arched 

 dorsally, subplane actinally, hence more semicircular in section, or if angles appear 

 there are generally seven. 



In Sclerasterias the ambulacra! ossicles are less compressed. In Astrometis, in a 

 space of 10 mm. near but not exactly at base of furrow, there are 19 or 20 plates and 

 16 in a comparable example of Sclerasterias. 



In true Orthasterias, which is far removed from Astrometis, the inner as well as 

 outer inferomarginal spine bears a cluster of crossed pedicellariae, as also do the 

 prominent actinal spines; the adoral carina is narrow and is composed of upwards 

 of five pairs of contiguous adambulacral plates; the actinostome is sunken; the 

 crossed pedicellariae are larger, without an enlarged terminal tooth. 



ASTROMETIS SERTULIFERA Xantns 



Plate 55, Figures 1, la, lb, 2, 2a, 4, 4rc-4e, 5, 5a; Plate 56, Figures 1, la-lf, 3; Plate 57, Figures 2, 2a, 



3, 4; Plate 58; Plate 59, Figures 2, 3 



Aslerias sertulifera Xantus, Proc. Acad. Nat. Sci. Philadelphia, 1860, p. 568. — Ives, List 



Cab. Stearns 1S90, p. 2 (according to Verrill). 

 Asterias forreri Jennings, Univ. Calif. Puhl. Zool., vol. 4, 1907, pp. 53-1S5, 19 text fig. — II. L. 



Clark, Echinoderms from Lower California, etc., Bull. Amer. Mus. Nat. Hist., vol. 32, 



1913, p. 203; Echinoderms from Lower California: Supplementary Report, Bull. Amer. 



Mus. Nat. Hist., vol. 48, 1923, p. 153. 

 Coscinasterias sertulifera Baker [Fisher], Some Echinoderms collected at Laguna, First 



Annual Report of Laguna Marine Laboratory, 1912, p. 89. 

 Marlhasterias (?) sertulifera Verrill, Shallow-water Starfishes, etc., 1914, p. 100. 

 Orthasterias dawsoni Verrill, Shallow-water Starfishes, etc., 1914, p 175, pi. 23, figs. 1, 2; 



pi. 75, figs. 2-26; pi. 80, figs. 2, a-g; pi. 81, figs. 3-36. 

 Orthasterias [Stylasterias] gonolena Verrill, Shallow-water Starfishes, etc., 1914, p. 184, 



pi. 67; pi. 68, fig. 1; pi. 69, fig. 2; pi. 82, figs. 3-36, 4-4a. 

 Astrometis sertulifera Fisher, A Preliminary Synopsis of the Asteriidae, etc., Ann. Mac Nat. 



Hist., ser. 9, vol. 12, 1923, p. 254. 



Diagnosis. — Rays five, occasionally six, more evenly rounded dorsally than angu- 

 lar, often swollen, constricted basally, slightly tapered, bluntly pointed; dorsal spines 

 in three to five series proximally, three distally, prominent often bristling; superomar- 

 ginal spines longer than dorsals; carinals frequently on several consecutive plates 

 proximally; two prominent chisel-form or slightly gouge-shaped inferomarginal 

 spines; a variable number of actinal spines in mature examples; distal adambulacrals 

 frequently monacanthid; first pair of post-oral adambulacral plates conspicuously 

 larger than second, which are in partial or full contact. In life, flexible and quite slimy. 

 E81 mm. ;r 13.5 mm.; R = 6 r; breadth of ray at base, 11 mm.; at widest part, 13 mm. 



Description.— The rays of carefully killed alcoholic specimens are evenly arched 

 and slightly to decidedly swollen, depending upon the condition of the gonads. In 

 one specimen with very much enlarged gonads the height of the rays is greater than 

 the width. The actinal surface is subplane, and the width is increased by the ventro- 

 lateral fringe of spines. The dorsal spines stand in three regular rows or sometimes 

 (as in Verrill 's cotype of gonolena from San Diego) there may "be a second short 

 dorsolateral series near the base of the ray, with upwards of five spines in the series; 



