14 NATURAL HISTORY BULLETIN 



The first three families are represented in depths less than 150 

 fathoms, though all except the first family are essentially deep- 

 sea groups. 



Family Asteriid^e Gray (emended). 



Asteriidce Gray, Ann. & Mag. Nat. Hist., vi, p. 178, 1840; Synopsis, p. i, 

 1866. Perrier, E^vis. Stell., Arch. Zool. Exper. et Gen., iv, p. 302, 

 1875; Mem. Etoiles de Mer, pp. 167, 198, 1876. Viguier, Squellette 

 des Stellerides, pp. 93, 99, pi. v, figs. 1-10, 11-12, 1878. 



AsteriidcB (emended) -|- StichasterickB Sladen, Voyage ChalL, xxx, pp. 430, 

 560, 1889. Perrier, Exp. Trav. et Talisman, pp. 43, 105, 107, 128, 

 1894; Contrib. l'«tude des Stellerides Atlan. Nords, pp. 25, 31, 1896. 

 Verrill, Monog. Starfishes, North Pacific, pp. 27-44, 1914a (emended.) 



Stellate starfishes, most often with five or six elongated rays; 

 sometimes with a variable number of unequal rays in autotomous 

 species; sometimes with numerous rays, increasing with age by 

 the outgrowth of interpolated rays, as in Heliaster and in Pycno- 

 podia. Madreporic plate generally single in five-rayed and six- 

 rayed forms, but often two or more in those with a variable num- 

 ber of rays, due to autotomy or budding. Dorsal and actinal 

 plates various in form and arrangement, most often reticulated. 

 Odontophore usually formed of a single piece. Oral ambulacra] 

 plates elongated and forming the jaws. Those along the grooves 

 become very short and compressed. Papulae occur both on the 

 actinal and dorsal sides. Ambulacral feet usually crowded in 

 four rows, sometimes more. Pedicellariae of two kinds are pres- 

 ent. Dorsal plates generally bear spines or spinules, various in 

 size and kind, and sometimes granules. They are never true 

 paxillge. 



The minor pedicellarise may be attached directly to the in- 

 tegument, either singly or in clusters, or to the spines, to the 

 pedicels of the larger forms, to saccular dermal growths around 

 the spines, to the inner edge of the ambulacral grooves, or rarely 

 even to the ambulacral feet. They are most commonly attached 

 by slender and sometimes long pedicels, and aggregated into 

 wreaths or clusters attached to a contractile fold of dermis on 

 the spines. They are often so abundant, in the wreaths around 

 the dorsal spines, that they nearly or quite conceal the spines 

 and integument in living specimens. In some cases they are at- 

 tached in large numbers to large muscular dermal sheaths or 



