218 BULLETIN 76, UNITED STATES NATIONAL MUSEUM 



spines; inferomarginals with one to three spines; one to three series of actinal plates, 

 usually two or three; one will defined though sometimes irregular series of dorso- 

 lateral plates; adambulacrals very regularly diplacanthid Uniophora Gray. 



b 2 . Adambulacral plates monacanthid; dorsolaterals not very numerous, trilobed, in one or two 

 fairly regular scries, more or less concealed by integument; superomarginals very broad; 

 inferomarginals (each bearing an oblique comb of two to four prominent spines) form a 

 sharp ventrolateral border to ray; an inconspicuous series of actinal plates; rays short 



and thick; gonads open ventrally Calvasterias Perrier. 



a 2 . Abactinal skeleton an irregular net with meshes of various sizes, the plates being sometimes 

 closely but irregularly imbricated by their lobes; abactinal plates not in rather obvious 

 longitudinal series (but occasionally in more or less evident transverse series); carinal series 

 usually but not always distinguishable and frequently very irregular; body sometimes cov- 

 ered by a pulpy skin which obscures the plates and sometimes even the spinelets. 

 6 1 . Adambulacral plates with two, rarely three spines, which never cany attached pedicellariae, 

 although large and small straight pedicellariae may occur on the surface of the plates or 

 on fleshy peduncles attached to plates near base of spines; clusters of the latter in dried 

 specimens occasionally appear to spring from the spine-sheath, but in reality do not. 

 c l . Abactinal plates and spinelets normally developed; both series of marginal plates nor- 

 mally developed. 

 d'. An actinolateral chevaux-de-frise of inferomarginal spines in transverse series of three or 

 four; abactinal spinelets numerous, small, close-set; superomarginal spines small, 

 not forming a well-differentiated, single or double longiseries; pedicellariae scat- 

 tered, not in circlets at base of spines, nor on sheaths surrounding spines; skin not 

 thick or puffy. 

 e'. Actinolateral spines devoid of attached pedicellariae; actinal spines in one series or 



absent; gonads opening dorsally Smilasterias Sladen. 



e 2 . Actinolateral spines carrying pedicellariae; gonads opening ventrally; paedophoric; one 



series of actinal spines Neosmilaster Fisher. 



<P. Superomarginal, inferomarginal, and actinal spines forming longiseries with circlets or 

 bouquets of pedicellariae; abactinal crossed pedicellariae associated with spines, in 

 circlets or attached to the base. 

 e 1 . Spinelets slender, mobile, more or less sheathed with soft skin carrying crossed pedi- 

 cellariae; gonads opening ventrally; young brooded by adult; superomarginals 

 monacanthid or diplacanthid; inferomarginals monacanthid or diplacanthid; one 

 or two series of monacanthid actinal plates (exceptionally spineless); adambula- 



crals regularly diplacanthid Diplasterias Perrier. 



e 2 . Spinelets coarse, tuberculate, sometimes very large, capitate or globose; skin not soft 

 or pulpy; gonads opening dorsally; actinals in one to three series. .Uniophora Gray. 

 c 2 . Either the superomarginal plates, or those of both series, not easily distinguishable; abacti- 

 nal skeleton well developed; inferomarginal spines not in close-set transverse series. 

 d l . Only the inferomarginals, of the two series, clearly distinguishable; to them are joined 

 small lateral transverse arcs (containing the superomarginals) separated, consecu- 

 tively, by broad papular areas or skeletal spaces; abactinal skeleton an irregular 

 network of plates, without indication of a carinal series; abactinal and inferomar- 

 ginal spinelets slender, cylindrical, in small groups; two long adambulacral spines; 

 ambulacral furrows wide, with large 4-ranked tube feet; rays 9 or 10. 



Saliasterias Koehler. 

 (P. Marginal plates not superficially distinguishable; a close granulation more or less uni- 

 form, without serial arrangement, interspersed with scattered pedicellariae, overlies 

 relatively large three to five lobed plates in an irregular abactinal reticulum; mar- 

 ginals four lobed; an incomplete series of actinals; size small; gonads opening ven- 

 trally. (Includes Hemiasterias Verrill, type G. biseriatus Koehler.) 



Granaster Perrier. 



