te 
REPORT ON THE ASTEROIDEA. 209 
are about ten or eleven in number, and decrease in size adorally and aborally. Of the 
mouth-spines proper, situated on the free margin of the plates, the innermost three on 
each side of the suture-line are long, robust, cylindrical, obtusely rounded, and form, 
together with the corresponding spines of the companion plate, the comb which stretches 
horizontally over the mouth-aperture. On the remaining portion of the free margin are 
three or four small, equal-sized, cylindrical spines. The first adambulacral plate next to the 
mouth-plate is narrow, with a biserial armature, consisting of about eight small, compressed, 
shghtly flaring, and truncate spines in each row. 
The madreporiform body is transversely oval in form, and not more than its own 
breadth distant from the marginal plates. 
The terminal plate is large and broad, very deeply channelled anteriorly, and with two 
or three short robust spinelets, which curve slightly over the furrow. 
Colour in alcohol, very light ochre-brown, almost verging towards grey. 
Locality.—Station 75. Between the islands of Fayal and San Jorge (Azores). 
July 2, 1873. Lat. 38° 38’ 0” N., long. 28° 28’ 30” W. Depth 450 fathoms. Volcanic 
mud. Surface temperature 70°°0 Fahr. 
Remarks.—This species is characterised by the single short, compressed, lateral spine, 
with two closely placed small companions, by the broad and flaring spinelets on the actinal 
surface of the adambulacral plates, and by the absence of an aboral line of spinelets on 
the infero-marginal plates. The form is very nearly allied to Astropecten irregularis, 
Linck, but is distinguishable by many points of detail when examples of the two species 
are compared side by side. 
9. Astropecten irregularis, Linck. 
Astropecten irregularis, Linck, 1733, De Stellis marinis, p. 27, tab. vi. fig. 13. 
Asterias aranciaca, O. F. Miiller, 1776, Zool. Dan. Prod., p. 234, No. 2831. 
Astropecten Miilleri, Miiller and Troschel, 1844, Archiv f. Naturgesch., Jahrg. x., Bd. i. p. 181. 
Astropecten echinulata, Miiller and Troschel, 1844, Archiv f. Naturgesch., Jahrg. x., Bd. i. p. 181. 
Localities. —“ Porcupine” Expedition ; 
Station 18. Off the west coast of Ireland, north-west of Achill Head. Lat. 54° 15’ N., 
long. 11° 9’ W. Depth 183 fathoms. Bottom temperature 9°'7 C. ; surface temperature 
TI 8-€; 
Station 46. Between Scotland and the Faerée banks. Lat. 59° 23’ N., long. 7° 4’ W. 
Depth 374 fathoms. Bottom temperature 7°°7 C. ; surface temperature 12°'1 C. 
Station 67. East of the Shetland Islands. Lat. 60° 32’ N., long. 0° 29’ W. Depth 
64 fathoms. Bottom temperature 9°°5 C.; surface temperature 11°°0 C. 
Station 68. East of the Shetland Islands. Lat. 60° 23’ N., long. 0° 33’ E, Depth 
75 fathoms. Bottom temperature 6°°7 C.; surface temperature 11°°4 C. 
Remarks.—These are all small forms and have a certain facies of their own, but they 
(ZOOL. CHALL. EXP.—PART LI.—1888.) j 27 
