186 
THE VOYAGE OF H.M.S. CHALLENGER. 
however, their number is very limited. As is pointed out in the diagnosis, the larger 
pedicels form a distinct simple row along each side of the body. These larger pedicels 
have a length of 7 mm. or more, and a breadth of 1 ‘5 mm. or less. The pedicels of the 
odd ambulacrum are so small that they are scarcely visible to the naked eye. The 
few and very scattered dorsal ambulacral appendages present, perhaps, a conical form, 
which, however, is by no means well marked ; they do not attain the size of the large 
lateral pedicels above mentioned. The middle of the odd interambulacrum seems to be 
almost naked. The tentacles are drawn within the body, but seem- to have the structure 
common to the Aspidochirotse. 
The calcareous ring (PI. X. fig. 16) is devoid of any posterior prolongations. A 
single short ventral Polian vesicle is present. The single dorsal madreporic canal is 
attached to the dorsal mesentery. A bundle of short, slightly branched, slender genital 
tubes is situated on the left side of the dorsal mesentery. The two respiratory- trees are 
well developed, but are not in any intimate connection with the pseudhaemal vessels. 
The longitudinal muscles are simple, and there are no retractors. 
The tables vary greatly in size and shape, some having a nearly regular hexagonal 
disk with six large peripheral holes and a central smaller hole, others having the disk 
smaller, irregular, with the central hole larger than the surrounding ones (PI. X. fig. 17). 
The diameter of the largest disks measures about 0T2 mm., while that of the smaller is 
only 0'07 mm. The height of the spire (PL X. fig. 18) varies from 0T2 mm. to 0’18 mm . 
But tables are often met with which have the disks perforated with more than six peri- 
pheral holes. The pedicels and dorsal appendages (pedicels ?) are strengthened by 
terminal plates and more or less deformed tables, but they seem in general to be devoid 
of transverse rods. The terminal disks of the dorsal appendages are more rudimentary. 
The above diagnosis and description refer to the large, w^ell-developed individual. The 
smaller specimen, 57 mm. long, obtained at the same Station is much contracted and 
wrinkled, but here it becomes more evident that the dorsal appendages at the anterior 
extremity of the body are of a conical form. 
The two specimens brought home from Station 298 resemble the small one obtained at 
Station 300 ; one of them, however, is devoid of deposits in the integument, probably a result 
of the infiuence of some acid in the alcohol. In the other specimen, on the contrary, the 
greater part of the deposits is left uninjured ; they closely resemble those above described, 
excepting that the three teeth of the spire are less spinose. The individual deprived of 
deposits seems to have the dorsal ambulacral appendages more numerous and hke pedicels. 
Holothuria murrayi, var. ^arva, nov. (PI. IX. fig. 2 ; PI. XVI. figs. 4, 5). 
Habitat . — Station 219, March 10, 1875 ; lat. 1° 54' S., long. 146° 39' 40" E.; depth, 
150 fathoms ; coral mud ; one individual. 
