BIOLOGY. 
Spong. 13 
General account of Sponges, with a special description of the fresh-water 
sponge, and of preparations of Sycandra raphanus, Oscarella lobularis , 
and other siliceous sponges ; Kukenthal (34) p. 32, and pp. 36-45.— 
General structure of Euplectella ; Ijima (29) pp. 37-57.—General anatomy 
of the Bath-Sponge ; Seurat (52) pp. 258-261. 
(ii) External Characters. 
(a) Attachment .—-Malacosaccus floricomatus, n. sp., lives fixed in 
the mud by a long stalk; so also, probably, M. unguiculatus F. E. S.; Top- 
sent (58) p. 450. 
(b) Form and Mode of Growth.—Parietal ledges and “cuff” of 
Euplectella , Ijima (29) p. 40. 
(c) and (d).—Nothing special. 
(iii) Anatomy of the Soft Tissues. Canal-System , 
Canal-System of sponges in general; Kukenthal (34) pp. 36-38. 
Anatomy of Sycandra raphanus , with an original figure ; Kukenthal 
( 34) pp. 42 & 43, fig. 34.—Canal-system of f Amblysiphonella lorentheyi , 
n. sp., p. 20: of + Corynella raujji , n. sp., p. 9: of t Myrmecidium hindei , 
n. sp., p. 10: of f Oligoccelia zitteli , n. sp., p. 18 : of + Steinmannia semseyi , 
n. sp., p. 14 ; VlNASSA de Regny (61). 
Canal-Systems of Miocene siliceous sponges ; Malfatti (40) pp. 
279-281. 
Body-wall of Hexactinellids composed of (1) the external trabecular 
layer, (2) the layer of chambers, and (3) the internal trabecular layer ; 
these three layers are made up histologically of two kinds of differentiated 
tissue, the flagellated chamber-wall or membrana reticidaris , composing 
(2), and the trabeculae, composing (1) and (3); p. 41. General arrange¬ 
ment of the soft parts of Euplectella marshalli , and their relation 
to the spicules. The entire thickness of the sponge wall is composed 
of “a nearly uniform network of thin trabeculae which keep the folded 
chamber layer suspended midway between the two surfaces of the wall.” 
Both excurrent and incurrent canals are simply intertrabecular spaces ; 
the former are direct continuations of the gastral cavity into the hollows 
of the folds of the chamber-layer ; the latter are lacunae pervading the 
recesses between the folds. The ectosome is a part of the general trabe¬ 
cular system ; the most superficially situated trabeculae form the dermal 
membrane. The endosome is similar in structure. Spicule-rays never 
pierce the chamber-wall, but lie between the chambers; pp. 117-128. 
Oscula and sieve-membranes of Euplectella , p. 38, footnote. Bottom- 
plate or inferior sieve-plate of Euplectella , p. 40. Corona of Regadrella 
komeyamai , derived from a sieve-plate, pp. 253 & 254, 267 & 268; Ijima 
(29).' 
Anatomy and Canal-System of Tetkya. The flagellated chambers open 
into the efferent canals by wide openings (apopyles), not by special ducts 
(aphodi), pace Lendenfeld. The medullary portion of the sponge consists 
throughout of chamber-tissue, and a special central portion containing 
genital products (as described by Delage) is not to be distinguished ; 
Maas (38) p. 267. 
Canal-System of Spongilla ; Kukenthal (34),. pp. 38-40 : of Pachy- 
dictyum globosum , n. g. n. sp. of Spongillince , p. 189 : of Spongilla sara- 
sinorum n. sp. and S. (?) vasta n. sp., pp. 197 & 200; Weltner (62). 
Of the Bath-Sponge; Seurat (52) p. 259. Anatomy of Oscarella lobularis ; 
Kukenthal (34) pp. 43 & 44. Canal-System of Halisarca clujardini var. 
magellanica ; Topsent (60) pp. 44 & 45. 
