354 
THE VOYAGE OF H.M.S. CHALLENGER. 
Family II. Anomocladida:, Zittel. 
Anoplia in which the desma is acrepidal, a variable number of smooth, cylindrical 
cladi radiate from a thickened centrum ; zygosis occurs between the expanded ends of 
the cladi of one desma and the centrum of another. 
Vetulina stalactites, 0. Schmidt. 
VetuUna stalactites, O. Schmidt, Spong. Meerb. Mexico, p. 19, pi. i. fig. 1; pi. ii. fig. 9, 1879. 
„ ,, Sollas, Ann. and Mag. Nat. Hist., ser. 5, vol. xv. p. 236 ; Proc. Roy. 
Irish Acad., ser. 2, vol. iv. p. 486, 1885. 
Sponge . — A sinuous folded plate, more or less cup-like, attached, surface of both 
sides even, meeting a flat upper margin at right angles ; outer surface marked by con- 
centric lines of growth ; pores and oscules both small, the latter generally distributed on 
the inner face, the former over the outer. Wall from 5 to 20 mm. in thickness ; con- 
sistence of stony hardness. 
Spicules. — I. Megascleres. 1. Desma, cylindrical cladi seldom bifurcating, varjdng 
from two to eight in number, smooth, or bearing rounded or irregular tubercles, termin- 
ating in expanded syzygial ends, 0‘1 to 0’15 by 0’012 to 0'02 mm.; centrum massive, 
0'05 to 0'07 mm. in diameter; when the cladi are less than six in number, produced 
into numerous branching twig-like processes from the distal face. 2. Strongyle, cylin- 
drical, 0'35 by 0'004 mm. 
The desmas are arranged with the acladose face of the centrum turned towards the 
outer surface of the sponge, and the cladi extended in the opposite direction; they terminate 
by abutting on the acladose face of the centra of the next succeeding layer, and thus 
form a series of groin-like arches. 
Habitat . — Barbados; depth, 100 fathoms (0. Schmidt). Probably also from shallow 
water, since a specimen exists in the Bristol Museum that was obtained long before the 
dredge was generally used for collecting, certainly before it was used in deep water. 
