123. 
128. 
BIBLIOGRAPHY. 23 
1874 Ruror, A. Note sur la découverte de deux Spongiaires de l’Etage 
Bruxellien des environs de Bruxelles (Ann. de la Société Malaco- 
logique de Belgique, Tome ix, pp. 1—14, Pl. 3). 
Numerous siliceous accretions occur in these Tertiary beds, which are 
largely composed of the detached spicules of siliceous tetractinellid Sponges. 
These accretions are erroneously regarded as definite Sponges, and on them 
two species are based, Stelletta discoidea and Dysidea tubulata. 
. 1874 Wrvitte-Taomson, C. The Depths of the Sea. 
The essential similarity in the minute skeletal structures of recent hexac- 
tinellid Sponges and of the Ventriculites of Toulmin Smith, is pointed out. An 
erroneous comparison is made between the general structure of Calosphera 
tubifew, a recent monactinellid Sponge, and Choanites, a fossil lithistid, the 
body-canals of this latter form being mistaken for tube-like processes, present 
in the existing Sponge. 
. 1874 Davey, EH. C. The Sponge-Gravel Beds at Coxwell near Faringdon. 
A general description is given of the deposit, and reference made to the 
Sponges with which it is filled; they are placed in the obsolete genera Manon, 
Tragos, &e. 
. 1874 Mayy, L. Silurische Schwimme und deren eigenthiimliche Verbrei- 
tung, ein Beitrag zur Kunde der Geschiebe (Zetts. d. deutsch. geol. 
Gesell., vol. xxvi, pp. 41—58). 
Treats of the state of preservation and mineral condition of the fossil 
Sponges in the Drift deposits of the Island of Sylt. 
. 1875 Gimpet, C. W.  Beitriige zur Kenntniss der Organisation und 
systematischen Stellung von Receptaculites (Abh. der k. bayer. 
Akad. der Wiss., II Cl., Bd. xii, 1 Ab., pp. 169—215, Pl. A). 
A minute detailed description of the characters of the genus is given, its 
thick inner and outer walls are stated to consist of individual plates held in 
position by intervening pillars, and a branching canal-system is also present. 
The genus is included in the Foraminifera in close relationship to Dactylopora. 
The genus Ischadites is regarded as similar generically to Leceptaculites, 
and Protospongia is also a related form. 
1874-75 Barrots,Ox. Sur la Philogénie des Eponges (Ann. Soc. Géol. Nord, 
pp. 71—73). 
Refers to the presence of lithistid spicules in Devonian Sponges, and the 
abundant development of the hexactinellide in the Chalk, and of the Corticatz 
