30 THE VOYAGE OF H.M.S. CHALLENGER. 
Young Phase.—In the small example above referred to (from Station 9 of the 
“Triton” dredgings, 608 fathoms), the spinulation of the abactinal surface is decidedly 
papilliform and well-developed. On the adambulacral plates there are already two large 
spines on the actinal surface, together with traces of a small companion in the same series. 
There are five or six spinelets in the furrow series. The pedicellaria is large and already 
characteristic. On the mouth-plates there is a marginal series of eight spines on each, the 
innermost being much larger and stouter than the others. The paxille of the abactinal 
surface are comparatively large and compact, composed of low robust papilliform spinelets, 
of which in the largest paxillee there are from nine to twelve. The central one, when 
present, is equal to the others, and not large and prominent, as in the adult. The anal 
aperture is large and distinct, and decidedly excentral in position. 
Localities —“ Porcupine” Expedition : 
Station 54. In the Faerbe Channel. Lat. 59° 56’ 0” N., long. 6° 27/0” W. Depth 
363 fathoms. Bottom temperature 0°3 C.; surface temperature 11°°4 C. 
Off Valentia, 100-150 fathoms. 
“ Knight Errant ” Expedition : 
Station 8. In the Faerbe Channel. August 17, 1880. Lat. 60° 3’ 0” N., long. 
5° 51’ 0” W. Depth 540 fathoms. Ooze. Bottom temperature 29°:2 Fahr. ; surface 
temperature 56°°5 Fahr. 
“Triton” Expedition : 
Station 9. In the Faerée Channel. August 23, 1882. Lat. 60° 5’ 0” N., long. 
6° 21’ 0” W. Depth 608 fathoms. Bottom temperature 30°°0 Fahr. 
2. Pontaster planeta, n. sp. (Pl. X. figs. 1 and 2; Pl. XIII. figs. 1 and 2). 
Rays five. R=37mm., r=6'5 mm. R> 5‘5r. Breadth of the ray near the base, 6 mm. 
Rays elongate, narrow, tapering continuously up to the extremity. Interbrachial arcs 
well rounded. Abactinal surface subplane, slightly convex along the median radial line. 
Actinal surface of disk convex, prominent at the mouth-angles, sloping thence to the 
margin, and slightly along the rays to the extremity. 
The paxillee of the abactinal surface are small, numerous, and tolerably well spaced. 
Midway along the ray the crown is composed of four to six short papilliform spinelets, the 
larger ones with a central elongate and tapering spinelet, which appears to increase in 
proportional length towards the extremity of the ray. Within the area of the disk larger 
paxille: are more frequently interspersed amongst the small ones, some of them with eight 
or nine spinelets surrounding the larger central one. The spinelets throughout are small 
and delicate. No pedicellarize are present on the abactinal surface. 
The supero-marginal plates, thirty to thirty-two in number from the median inter- 
radial line to the extremity, form a narrow and inconspicuous border when viewed from 
