no. 1827. NEW GENERA OF STARFISHES— FISHER. 427 



as this spine. Aperture papillae short, broadly ovate, with a mem- 

 branous envelope produced into a short blunt sacculus. The cal- 

 careous part is only about one-fourth tlie length of the adjacent 

 subambulacral spine, and there is no difference between the papillae 

 of the two sorts of plates. The apertures are narrow and not 

 completely covered by the papillae. The first adambulacral plate, 

 sometimes prominent, sometimes nonprominent, has 2 equal or 

 unequal spines and a large aperture papilla immersed in the actino- 

 lateral membrane. 



Mouth plates small and very high, the combined pair produced 

 actinally into a conical eminence, the apex of which is situated at 

 the middle of the median suture. The height of this extraordinary 

 beak or cone equals the interradial diameter of the pair of plates. 

 From the blunt point at the top the plates slope straight and steeply 

 to the actinostomial margin, which is produced into a slight beak, 

 but in the opposite direction the plates diverge, leaving an open 

 suture, and the margin of the plates is arcuate and nearly perpen- 

 dicular. Marginal spines 3 or 4, the lateral-most the strongest 

 and longest, situated on a slight angle of the margin and directed 

 across mouth of furrow. The innermost spine which is well spaced 

 from the median beak of actinostomial margin is nearly as long as 

 the lateral-most and the 1 or 2 intermediate spines are some- 

 what shorter. Suborals 2, nearly like the subambulacrals and situ- 

 ated in a line parallel to and near median suture, on the actino- 

 stomial face of the cone. 



Actinolateral membrane translucent forming a broad margin 

 which decreases in width evenly from interradial angle. The four- 

 teenth spine is the longest, and is the first to meet the free edge of 

 membrane. The first is articulated to the second adambulacral. 

 The spines do not meet interradially their fellows of adjacent ray, 

 but leave a narrow wedge-shaped area. The length of this wedge 

 (the apex touching mouth plates) is about half the extent of the free 

 edge of one ray measured along edge of actinolateral membrane. 

 This actinolateral membrane is nearly flat. 



Madreporic body globular, and without a paxilla on its surface. 



Type-locality. — Station 5623, Molucca Passage between Gillolo and 

 Makyan Islands, 272 fathoms; fine sand, mud. 

 Type.— Cat. No. 28660, U.S.N. M. 



