HEXACTINELLIDA. L9 
The monoxyhexasters (VI. 3e”) are fairly common; they are about 100p in diameter. 
The calycocomes (VI. 3f, f') are 2204 in diameter, the primary rays being 14y in 
length ; the solid hemispherical cup-shaped capitulum is 9 in length and breadth ; 
the secondary rays form a plume-like circle of six to eight slender, slightly divergent 
rays, tipped with very small disks. 
Holodiscohexasters (VI. 3g), 96m in diameter, are very rare; the short primary 
rays, 9 in length, divide into two to four secondary rays ending in disks with four 
to five sharp recurved teeth. The microdiscohexasters (VI. 3h) are 40p in diameter. 
This new species closely resembles A. pilosa in its outward appearance, but differs 
from that species chiefly in the structure of the gastral membrane (VI. 3), and in the 
absence of the holoxyhexasters, so abundant in A. pilosa. 
Numerous macerated fragments, consisting solely of a skeletal framework of 
bundles of diactins with large hexactins, and occasionally autodermal pentactins, were 
obtained from 10-20 fathoms in McMurdo Bay. These, together with a sack-shaped 
skeleton and a tuft, 20 cm. in length, of diactin and anchor-like pentactin basalia, found 
by a sledge party on the ice, all belong to Awlorossella levis, 
Winter Quarters : (1) two large specimens taken in the trawl 150 yards south of 
the ship, in 18-36 m. (10-20 fms.) ; (2) two small young specimens from No. 5 hole 
(Seal Hole), August 7, 1902, 325 m. (178 fms.); (3) Macerated fragments from 
MeMurdo Bay, 18-36 m. (10-20 fms.). 
AULOROSSELLA LONGSTAFFI.* 
(Plate II., fig. 4, and Plate VIL., figs. la—k.) 
Sponge barrel-shaped, almost solid, with only a very shallow gastral cavity with 
wide circular orifice having a thin unarmed edge. Surface irregularly tuberculated and 
ridged, pleuralia almost entirely absent (there being only two or three scattered about). 
Inferior end without a definite root-tuft, but with a few large conules with a few 
basalia. Autodermalia thick pentactins, autogastralia thick hexactins. Amongst the 
parenchymalia curious tetractins. 
The sole specimen of this interesting species is 6°8 cm. in height, 3°9 em. in 
breadth about the middle; the orifice is nearly 2 cm. in diameter, and the gastral 
cavity only 1°4 cm. in depth. In its stumpy fleshy appearance, the specimen some- 
what resembles a kind of cactus plant. Both the dermal and gastral surfaces are 
smooth and glistening, and almost opaque, scarcely showing any trace of a hypogastral 
network. The shallow gastral cavity has in its floor two depressions separated by a 
ridge. 
The skeleton is mainly constructed of bundles of diactins; and in addition to 
these, large reeular hexactins are distributed in the sponge body. 
* The species name is given in honour of Mr. Longstaff, whose munificent donation of £25,000 made 
possible the fitting-out of the expedition, 
») 
VOL. III, 4 K 
