ASTEROIDEA OF H.M.S. ' OHALLEN&EE ' EXPEBITION. 205 



the outermost spine is attached to the prominent posterior or 

 aboral portion of the median keel of the mouth-plates, and there 

 coalesces with the web of the corresponding comb of the neii'-h- 

 bouring ray, thus forming an elegant compound pair of fans that 

 arch over the aboral peak of the plate. 



Actino-lateral spines rather short and robust, not extending, 

 or only to the very slightest degree, beyond the margin. They 

 are united by a fine semitransparent membrane, slightly indented 

 between the tips, which also forms the actinal floor of the test. 

 Probably in this species there is no free extension of the lateral 

 or marginal fringe, such as occurs in more shallow-water forms, 

 but unfortunately the preservation of the specimens in this por- 

 tion of their structure is imperfect. For the same reason it is 

 difficult to determine with accuracy the number of actino-lateral 

 spines, but probably about 20 to 22 were present : 17 -f may be 

 counted in natural position ; the sixth from the mouth appears to 

 have been the longest. 



Colour, in alcohol, brownish grey. 



Station 286. Lat. 33° 29' S., long. 133° 22' W. Depth 

 2335 f ms. ; bottom temperature 0°"8 C. ; red clay. 



Maesipastee hiesutus, n. sp. 



Marginal contour substellate, interradial angles well indented, 

 the lesser radius being in the proportion of 60'2 per cent. ; 

 i2 = 13'5 millim., r=8'5 raillim. Eadii broad at the base, bounded 

 by lines running direct from the arm-angle, with little if any 

 curve or rounding. Dorsal area moderately convex, radii slightly 

 upturned at the extremities. 



Supradorsal membrane a fine, irregular, and somewhat spon- 

 giose tissue continuous over the whole area, through which the 

 extremities of the spinelets of the paxillse protrude freely. No 

 definite membrane ; no muscular fibrous bands. Paxillsa with 

 long robust pedicels bearing 10 to 15 fine, long, acicular 

 spinelets ; investing membrane of the crown merging into the 

 general supra-dorsal tissue ; the naked tips of the spinelets 

 which pass through the tissue giving the surface a somewhat 

 hirsute or prickly appearance. Spiracula comparatively large, 

 very few in number, and very widely spaced. Oscular aperture 

 inconspicuous ; valves formed of spines similar to the rest of the 

 paxillse, and with no specialized external cliaracteristics, 



Ambulacral furrows broad and straight, not petaloid. Sucker- 



