13O FISHER 



External to adambulacral plates is a regular series of actinal 

 intermediate plates, and separated from the latter by a regular 

 series of papulae is a row of smaller inferomarginals. Some- 

 times a supermarginal series can be distinguished just above 

 the inferomarginals, especially on outer part of ray, where the 

 2 series are fairly regular. At base of ray the serial arrange- 

 ment is broken up and 2 or 3 additional series of small inter- 

 mediate plates are interpolated. The "marginal plates " are 

 larger than dorsolateral pseudopaxillas. 



Adambulacral plates separated by a distinct suture. Arma- 

 ture very dense, consisting of many spinelets, as follows: (1) 

 on furrow face of plates 2 to 6 small sabre-shaped spinelets in 

 a vertical series, or more irregularly in 2 series. The number 

 varies in different individuals. Usually there are 5 or 6 at base 

 of ray and 2 or 3 to each plate beyond middle. Occasionally 

 specimens have more than three on plates of distal portion of 

 arm. (2) On actinal surface of plate are 30 to 40 slender 

 pointed spinelets arranged in 3 or 4 transverse series on inner 

 half of plate, but too crowded on outer half to form rows. 

 Even the inner spinelets are often without regularity. Spine- 

 lets decrease rapidly in length and calibre from the furrow out- 

 ward, the outer spinelets being sharper than the inner and 

 about the same size as those on other actinal plates. 



Madreporic body prominent, tubercular, situated midway 

 between center of disk and interbrachial angle, there being 

 small spinelets scattered on the surface. Striations coarse, 

 irregularly radiating. 



Type, No. 21931, U. S. Nat. Mus. Type locality, Albatross 

 Station 2936, off Dan Diego, Cal., in 359 fathoms, on mud. 



Family SOLASTERIDiE Perrier. 

 Genus Crossaster Miiller & Troschel. 



Crossasier Miiller & Troschel, Monatsber. d. k. preuss. Akad. 

 d. Wiss. Berlin, 1840, 103. 



a. Marginal plates of two kinds in a single linear series — conspicuous 

 transversely oriented, prominently spinous, paxilliform plates 

 alternating with 1 or 2 low longitudinally placed plates with 



