A. E. Yerrill — JRevision Genera and Species of Starfishes. 187 



Nereidaster symbolicus (Sla.), op. cit., p. 297, pi. 1, figs. 1, 2, pi. liii, figs. 7, 8, 

 1889. 



East Indies and Philippines, 28 to 140 fathoms. 



Nereidaster- bipunctus (Sla.), op. cit., p. 301, pi. lii, figs. 3, 4, pi. liii, figs. 11, 

 12, 1889. 



Oflf Admiralty I., 150 fathoms. 



Subfamily. PSEUD ARCH ASTERIN-ffi Sla. (emended). 



Pseudarchasterince Sladen, Voy. Chall., xxx, p. 109, 1889. 

 Astrogoniince {pars) Per., Exp. Trav. et Talism., pp. 337, 338, 1894. 



This subfamily is remarkable for combining, in various ways, the 

 structures that are generally characteristic and distinctive of Gonias- 

 teridae and Plutonasteridae. The intermediate character of the group 

 is so marked that Perrier and Sladen have differed as to its place- 

 Perrier placed it in his Pentagonasteridje, while Sladen placed it in 

 his Archasteridte. In fact, its affinities appear to be nearly evenly 

 balanced between the two groups. True pedicellaria?, which might 

 throw light on the subject, are generally absent from all the known 

 species of the typical genera. 



The abactinal radial plates are arranged in radial rows, the 

 medium ones larger. They are paxilliform, more or less columnar, 

 with round or elliptical convex tops, and with an enlarged six-lobed 

 or stellate basal portion, the projecting lobes articulating and leaving 

 spaces between them for the papular pores, which occupy large 

 radial areas. About six are arranged singly around each of the 

 plates. 



Marginal plates are thick, moderately large and paired ; they have 

 deep fasciolated sutural grooves between them. The dorsal plates 

 are rarely in contact medially, unless close to the tip of the rays. 

 They are covered with close granules or small, crowded, appressed 

 spinules, and the lower ones often have several larger central spines 

 of the same character, but in some species the plates are all evenly 

 granulated. 



The adambulacral plates are broad, and usually angular or convex 

 on the furrow margin, so that the furrow is constricted opposite 

 each pair, especially distally. The furrow spines are usually in a 

 curved or divergent series ; those of the actinal side may be in 

 longitudinal rows or clustered. 



The actinal plates are often numerous, angular, arranged in chev- 

 rons, with the rows parallel to the ambulacral furrows. More or less 



