ASTEROIDEA OF NOBTH PACIFIC AND ADJACENT WATERS FISHER. 167 



wholly ijranulated, small secondary plates wedged between tiie primaries. There 

 is a fairly distinct row on either side of the metlian radial series, and laterally from 

 this for three or four rows the secondaries arc numerous but not regular in occurrence. 

 From the inner side the primary plates are sli<;hlly stellate with blunt lobes; papulse 

 are single and absent from interradial areas. Marginal plates centrally bare; actinal 

 intermediate plates mostly subquadrate, covered with good-sized spaced C|uadrate 

 granules; adambulacral plates slightly wider than long with three or four subquadrate 

 furrow spines and behind these three rows of spines and granules, the armature 

 being graduated into actinal granulation. Man}" adambulacral plates bear a short 

 rather high pedicellaria with two oblong jaws. The abactinal plates have the 

 central part naked and convex, thougli some are wholly granulated. 



Verrill classifies this species in his restricted Tosia. The presence of the 

 abactinal secondary plates as well as of pedicellariie higher than those of typical 

 Tosia suggests the alliance of tlie form with the less spiny Goniasters. More speci- 

 mens will be necessary to clear up the limits of Tosia and Pentagonaster. If any 

 uniting of genera takes place it should be Goniaster, Pentagonaster, and Tosia, not 

 Tosia with Plinthaster or with Ceramaster. The two genera under discussion differ 

 quite widely from either Plinthaster or Ceramaster in the character of the abactinal 

 and actinal plates which in the Australian-New Zealand forms are naked and con- 

 vex (but not tabulate) and in the marginal plates which tend to have either one or 

 both series with enlarged distals. 



Sph^riodlscus Fisher." — Type, Stephanaster [= Pentagonaster] hourgetiViyrnt'v. 

 Marginal plates thick and wide, few, the penultimate or antepenultimate plate of 

 both series larger than the rest; niarginal plates with small spherical granules about 

 the borders, and over general surface are scattered spherical granules sunk in special 

 shallow pits; last two superomarginals in contact. The granules about borders of 

 plates are rather numerous, and in several series on the outer or lateral face of plates 

 of both dorsal and ventral scries. Abactinal plates flat-topped, only very slightly 

 tabulate on radial areas, covered with granules; papula; absent from center of disk 

 and a narrow interradial strip. Actinal intermediate plates wholly granulated. 

 Adambulacral plates wider than long, with four or five furrow spinelets; behind these 

 two or three thicker, shorter spinelets, and then five to eight granules. Pedicellarise 

 with two slender spatidate blades which rest in inconspicuous depressions. They 

 may occur on all the plates. Contains two species, Sphseriodi^cits bourgeti (Perrier), 

 Cape Verde Islands, and SpJiseriodiscus ainniopJiilu-s (Fisher), Hawaiian Islands. 



This genus differs from Pentagonaster in having the upper and lower plates 

 wholly granulated; in having not the ultimate but the penultimate or antepenulti- 

 mate marginals enlarged; in having marginals with spaced granules. The abactinal 

 plates are flat-topped and slightly tabulate on radial areas; the actinals are flat, 

 never convex. 



Goniaster Agassiz.* — Type. A. tessellata ]..amarck, by designation.'^ Verrill 

 (1.899, p. 1-50) has revised this genus. lie gives the type as ^r. cu-spidatu^ Gray, to 

 which species the Asterias tessellata of Lamarck may be restricted, as it is necessary 



a Ann. and Mag. Nat. ni.<t., ser. 8, vol. 5, Feb., 1910, p. 171. 

 6 Mem. 80C. 8(i. nat. Neiich.ltel, vol. 1, 1835, p. 191. 

 <■ Idem, p. 14.'). 



