42 
THE VOYAGE OF H.M.S. CHALLENGEE. 
Supplemental Account oe all other known Species of Tetillida: 
NOT IN THE Challenger Collection. 
Tetilla antarctica (Carter). 
Tethya antarctica, Carter, Ann. and Mag. Nat. Hist., ser. 4, vol. ix. p. 412, pi. xx., 1872; 
non Carter, Tethya antarctica, Phil. Trans., vol. clxviii. p. 287, 1879. 
Sponge globular ; oscules large, several ; pores in sieves generally distributed ; surface 
papillose with projecting spicules. 
Spicules. — I. Megascleres. 1. Oxea, 1’25 mm. long. 2. Protrisene. 3. Somal 
anatrisene, with hastately-shaped cladome. 4. Radieal anatrisene, with a grapnel-like 
cladome; rhabdome 37 '5 mm. long. 
II. Microscleres absent. 
Habitat. — Antarctic Ocean; lat. 74° 30' and 77° 30' S., long. 175° 0' W.; depth, 206 
to 300 fathoms. 
Remarks. — Carter has referred to this species a sponge obtained from 20 fathoms in 
Eoyal Sound, Kerguelen, distant about 120° of longitude and more than 20° of latitude 
from the locality which furnished the type. Beyond stating that the oxeate spicules of 
the sponge from Kerguelen are larger than those of the type. Carter gives us very little 
information about it. One of the characters of Tetilla antarctiea, however, is the 
absence of sigmaspires, and upon this Carter justly lays great stress, not only mentioning 
it in describing the species, but subsequently referring to it in the course of general 
remarks on the Tetillidse,^ and elsewhere. On examining preparations of the sponge from 
Kerguelen identified with Tetilla antarctiea, I find sigmaspires abundantly present ; 
this alone is sufficient to show that the identification is erroneous. Comparing its spicules, 
however, with those of Tetilla grandis in the Challenger collection, I find so marked a 
correspondence that I can scarcely doubt the identity of the second sponge referred to 
by Carter with this species. 
Tetilla arabica (Carter). 
Tethea arahica. Carter, Ann. and Mag. Nat. Hist., ser. 4, vol. iv. p. 3, pi. i. figs. 1-13, pi. ii. 
figs. 19, 20, 1869. 
Sponge spherical and free, or hemispherical and fixed ; surface hispid, irregularly 
reticulated with ridges ; pores in the depressions ; oscules several large, on conical 
eminences. Size about 75 mm. in diameter. 
Spicules. — I. Megascleres. 1. Oxea, 3 ‘5 by 0'035 mm. 2. Protrisene, rhabdome 
6‘4 by 0'014 mm.; cladi 0‘084 mm. long. 3. Anatrisene, rhabdome 4’5 by O’Ol mm.; 
cladi 0‘084 mm. long. 
’ Ann,, and Mag. Nat. Hist, ser. 5, vol. xi. p. 366. 
