"^'iSi!^,i:t" ^MMm in the Uni.

504
PROTOZOA.
II Spicules anchor-shaped or of pyramidal type :—Lithistida, Ancorinida,
Geodinida, and (extinct) Vermiculata.
HI Spicules monaxial, polyaxial, or wanting :—Halisarcina—Gumminece,
Ceraosponyia, Chalinea, Chalinopsida, Renierina, Suberitida, Desmacidina.
IV. Spicules calcareous :—Calcispongia.
The Hexactinellida are thus defined and subdivided by Kent (Month. Micr.
J. Nov. 1870, p. 252) :—
Order Hexactinellida, 0. Sdt. Sponges with a sihceo-fibrous or siliceospicular
skeleton. Spicula of sexradiate-stellate type invariably present.
Suborder I. Coralliospongia, J. E. Gray. Sponge-body supported by an
anastomosing or continuous reticulate skeleton. Reproductive gemmules entirely
membranaceous, nonspiculous (?). Genera: Euplectella, Habrodictyon,
Aphrocallistes, Farrea, Aulodictyon, Macandrewia, Dactylocalyx, Fieldingia.
Suborder II CaUcispongia, W. S. Kent. Sponge-body supported by an
interlacing or isolated spicular skeleton, never by a reticulate and continuous
one. Reproductive gemmules membranous, furnished with protective spicula
(?). Genera: Pheronema, Hyalonema, Askonema, Sympagella, Lanuginella,
Vazella.
Prof. E. PERCEVAL WRIGHT figures and describes an osculum of the spongemass
of Hyalonema mirabilis, and the arrangement of spicules connected
therewith (Q. J. Micr. Sc. 1870, p. 3).
Silicece.
Pheronema. Dr. Leidy figures (Am. Nat. March 1870) the sponge from
Santa Cruz to which, in 1868, he gave the name of Pheronema annee. Pheronema,
Leidy, = Holtenia, Wyville Thomson (Kent, Ann. N. H. August
1870, p. 184; see also Zool. Rec. vol. vi. p. 679). P. grayi, sp. nov., Kent
(I. c. pp. 182-186), Setubal, Portugal. Dr. Gray (I. c. p. 311) considers this
to be generically distinct from Pheronema, having the filiform anchoring spicules
(instead of being in tufts at the hinder end of the body) arising separately
from all parts of the surface, except a small broad nude band round
the oscule. Dr. Gray proposes for it the new generic name Callisphara ; but
Professor Wyville Thomson (P. R. Soc. xix. p. 153) considers it only a
variety of his Holtenia carpenter!.
Vazella, gen. nov., Gray (I. c. p. 311). To include Holtenia pourtalesii
and H. saccus, 0. Sdt.
Dr. GRAY proposes to form Pheronema and its allies into a new family,
Pheronemidse (I. c. p. 310).
Aphrocallistes bocagii, sp. nov., Perceval Wright (ibid. p. 4 ; see also
Kent, M. Micr. J. Nov. 1870, p. 248, and O. Schmidt, Spongien des atlantischen
Gebietes, p. 13), Atlantic, Cape-Verde Islands, ' Porcupine' Expedition,
&c.
Askonema, g. n., Kent (M. Micr. J. 1870, p. 245). Sponge-body bagor
cup-shaped, of felt-like consistence, composed of an interlacement of long
filiform siliceous fibres or spicula. Interspersed among these, hexradiate
spicula of various sizes and minute multiradiate ones with capitate extremities.
A. setubedense, coast of Portugal.
Aulodictyon, g. n., Kent (ibid. p. 249). In small fistulose ramifications;
basal skeleton consisting of a complex reticulated tube, between and con-