632 THE VOYAGE OF H.M.S. CHALLENGER. 
Localities. —Station 46. Off the coast of North America, east of New Jersey. May 6, 
1873. Lat. 40° 17’ 0” N., long. 66° 48’ 0” W. Depth 1350 fathoms. Blue mud. 
Bottom temperature 37°°2 Fahr. ; surface temperature 40°:0 Fahr. 
Station 47. Off the coast of North America, east of Massachusetts. May 7, 1873. 
Lat. 41° 14’ 0” N., long. 65° 45’ 0” W. Depth 1340 fathoms. Blue mud. Surface 
temperature 42°°0 Fahr. 
Station 50. South of Halifax, Nova Scotia. May 21, 1873. Lat. 42° 8’ 0” N., long. 
63° 39' 0” W. Depth 1250 fathoms. Blue mud. Bottom temperature 38°:0 Fahr. ; 
surface temperature 45°:0 Fahr. 
Remarks.—Freyella bracteata is distinguished by the number of its rays, by their 
comparative rigidity, by the proportionally short and robust lateral spines, by the char- 
acter and the small number of the spinelets on the abactinal plates, and by the character 
of the armature of the mouth-plates. 
6. Freyella dimorpha, n. sp. (Pl. CXY. figs. 1-5). 
Rays twelve. R=250mm.; r=10 mm. R=25r. Breadth of a ray at the base, 
4°7 mm.; at the widest part of the ovarial inflation, 8 to 9 mm. (measured at about 16 
mm. from the disk); at 50 mm. from the disk the breadth is 3°25 mm. ; and at about 
midway between the extremities, 2°5 mm. 
Rays very long and delicate, narrow and cylindrical at the base, and immediately 
swelling gradually into an elongately oval or subfusiform ovarial inflation, the tumidity 
of which is not great, and is of nearly the same dimension for some distance along the 
median part of the region; it contracts gradually outwardly and terminates at about 30 
to 32 mm. from the disk, thus occupying about the proximal eighth of the length. 
Beyond the ovarial region, the ray is subtriangular, with a truncate median carination, 
and tapers gradually to the extremity. The interbrachial ares are simple clefts. 
The disk is small, with the abactinal surface subplane and probably capable of slight 
inflation ; it is on a higher level than the abactinal surface of the rays, and the margin is 
sharply rounded and passes towards the basal part of the rays almost precipitously. The 
abactinal surface of the disk and of the rays as far as the ovarial region extends is covered 
with imbricating, subhexagonal plates, overlaid with a delicate membranous tissue. The 
plates are thin, but often comparatively large, and their greater diameter lies transverse 
to the direction of the ray. Each plate bears from five to ten (usually about half a 
dozen) very minute spinelets, from 0°35 to 0°45 mm. in length, covered with simple 
membrane and articulated on small miliary tubercles. The spinelets have a tendency to 
form lineal series along the major, transverse, diameter of the plates, especially on the 
lateral regions. Isolated sessile pedicellarize are to be found here and there upon the 
plates, though in some examples they appear to be wanting altogether. The disk has a 
