REPORT ON THE ASTEROIDEA. 7 
Chorological Synopsis of the Species. 
| 
Ocean, Range in Fathoms. Nature of the Sea-bottom. | 
Pararchaster armatus?. : Atlantic. |} 1250to 1350 | Blue mud. 
Pararchaster antarcticus : Southern Ocean. 1675 Blue mud. 
Me f Diatom ooze (1600 fathoms), | 
Pararchaster pedicifer . : Southern Ocean. 1600 to 1900 | Globigerina ooze (1900 fthms). | 
. ; { Green mud (565 fathoms). 
Pararchaster see rays 7 Pacific. 565 to 1875 ) Blue mud (1875 fathoms). 
LEGIREEOLSUE CUDA TEEN vate 1700 or 1240 | Blue mud. | 
var. occidentalis. a | | 
Pararchastér spinosissimus . Atlantic. 425 Volcanic sand. | 
| 
1. Pararchaster senisquamatus, n. sp. (Pl. II. figs. 1 and 2; PL IV. figs. 7 and 8). 
Rays five. R=166mm.;7=15mm. R=11,7. Breadth of a ray near the base, 
14°5 mm. 
Rays very elongate, comparatively narrow and flat, tapering gradually and slowly 
from the base to the extremity, the outer part being very attenuate. Disk very small. 
Abactinal surface plane, feebly convex or subcarinate along the median line of the rays. 
Lateral walls of the ray low and vertical. Actinal surface of the disk prominent at the 
mouth-angles, and sloping thence to the margin and very slightly along the rays. Inter- 
brachial ares widely rounded. 
The abactinal surface of the disk and rays is covered with small, uniform, subcircular 
seale-like plates, which are overlaid with a delicate membranous tissue. The plates bear 
on their centre a single minute subconical or cylindrical spinelet ; along the rays these are 
quite microscopic thornlets, but upon the disk and at the base of the rays there are a 
number of much larger spinelets; the largest are elongate, about 7 to 8 mm. in length, 
robust, tapering, and sharply pointed, and their position probably marks the primary 
apical plates; the primary radials and basals being especially distinguishable, and perhaps 
also the dorso-central and the under-basals; other spinelets rather smaller are present in 
the vicinity of these, but they rapidly decrease in size as they recede from the central 
area; and really definite spinelets do not extend further along the base of the ray than 
the third or fourth supero-marginal plate. 
The supero-marginal plates, fifty-five in number from the median interradial line to 
the extremity, are elongate and suboval in form, and are confined entirely to the lateral 
wall of the ray; their posture appears slightly oblique when viewed from the side, the 
aboral end of one plate standing over the adoral end of the next outward; their height is 
1 The exact station off the coast of Portugal is not recorded. 
2 It is uncertain whether this species is from Station 44 or Station 45. 
