SPONGIIDA. 
483 
ing many species of sponges, &c), while confirming James-Clark’s important 
observations {cf. Zool. Rec. iii. pp. G37, 644, v. pp. 676, 677) from observa- 
tions of his own on Grantia eompressa^ &c., is unable to discover sponge- 
cells in siliceous sponges (except Spongilla), owing to their smaller size. The 
sponge-cell (whose true mode of feeding is still somewhat doubtful) is at 
one time a flagellated infusorium, and at another a rhizopod, and is therefore 
intermediate between the two. He also describes and figures (pi. 2. f. 33- 
37) the structure of Cliona corallinoides, Hancock, and figures a group of 
Botryllus polycyclus (pi. 2. f. 41), pointing out the analogy between them 
and the sponges. He regards the osculum of the sponge as a vent, as it only 
serves accidentally for an influx of water, and not normally, as supposed by 
Hackel, whose views on the structure and classification of the sponges he 
criticizes. 
H. J. Carter remarks on the parasites of the sponges, and severely cri- 
ticizes Bower bank, whose Stematumenia is an Alga^ and his Halyphysema a 
Formninifer. Ann. N. H. (4) viii. pp. 330-332. 
E. Parfitt (Tr. Devon. Ass. 1870; cf. Q. J. Sc. n. s. i. p. 113) describes 
and figures 27 difierent sponge-spicules from the greensand of Haldon and 
Blacktown, near Exeter. Many of them are identical with those of recent 
species described by Boworbank in his ^ British Spongiadse and others closely 
resemble those of Euplcctolla aspergillum and Pheroncma {Iloltenia). 
M. Ponton (‘The Beginning, its When and its How,’ pi. M) figures various 
sponge-.spiciiles. 
Carpenter and Wyville Thomson’s researches on sponges are noticed, 
Arch. Sci. Nat. xli. pp. 81-83. 
Calcarea. 
Sycon ciliatiim. On its embryo, cf. Willemoes-Suhm, Z. wiss. Zool. xxi, 
p. 382, pi. 31. f. 4. 
Trichogypsia, g. n., Carter, Ann. N. H. (4) viii. p. 1. Massive, sessile, de- 
pressed. Surface uneven, rough, ridged, villous, presenting a single vent at 
one end of the ellipse, about midway between the border and the centre, at 
the bottom of an oval excavation, furnished internally with a circle of minor 
vents arranged round the large one. Spores scattered over the surface gene- 
rally. Internal structure close, areolar, accompanied by the branching ex- 
cretory canal-system. Spicules of one form only (no triradiate or quadri- 
radiate spicules), linear, sinuous, fusiform, spino-tuberculate at the extre- 
mities, arranged more or less perpendicularly. Type T. villosa^ sp. n., id. I, c. 
pi. 1. f. 1-4, on the deciduous capsule of a shark’s egg, S. Devon. 
Leuconia johnstonij sp. n., id. 1. c. p. 3, pi. 1. f. 6-12, coast of Devon (=sX. 
nivca, var., Johnst.). 
SiLlCEA. 
H. J. Carter, A Descriptive Account of three Pachytragous 
Sponges growing on the rocks of the South Coast of Devon, 
Ann. N. H. (4) vii. pp. 1-15, pi. 4, proposes the term Pachy- 
tragia to include the Corticatce of O. Schmidt and the Tethyada 
and Sph(jprospongia of Gray. The chondroid species, of which 
Tethya lyncurium is typical, with its repent or incrusting allies. 
