145. 
146, 
147. 
148. 
149. 
BIBLIOGRAPHY. 27 
1877 Zirren, K. A. Studies on Fossil Sponges, I, Hexactinellida (Annals 
and Mag. Nat. Hist., 4 §S., vol. xx, pp. 257—273, 405—424, 
501—517). 
Translated by W. 8. Dallas from the “ Studien ” in ‘ Abhand. d. k. bayer. 
Akad. der Wiss.,’ II Cl., Bd. XIII. 
1877 Zrrrer, K. A. Untersuchungen iiber fossile Spongien (Neues Jahrbuch, 
pp. 705—709). 
A short notice and criticism of the first part of vol. v of ‘Quenstedt’s 
Petrefaktenkunde.’ 
1877 Sonnas, W. J. On Pharetrospongia Strahani, a fossii Holorhaphidote 
Sponge from the Cambridge Coprolite Bed (Quart. Journ. Geol. Soc., 
vol. xxxill, pp. 242—255, Pl. xi). 
Gives a minute description of its structural characters ; it is composed of 
anastomosing fibres, which consist of minute acerate spicules, closely arranged, 
generally parallel to one another. The forms are now nearly entirely cal- 
careous, but in some cases a thin external film of the fibre with some of the 
spicules is siliceous. The Sponge is regarded as having originally been 
siliceous, and it is placed in the family Renierida. 
1877. Sortas, W. J. On the Structure and Affinities of the genus Siphonia 
(Quart Journ. Geol. Soc., pp. 7990—835, Pls. xxv, xxvi). 
The minute structure of the skeleton is fully described ; it is stated to 
consist of quadriradiate spicules with four diverging arms, bifurcating near 
their extremities and terminating in a number of rounded apophyses with 
intervening concavities. This structure is compared with that of the existing 
lithistid Discoderimia. Details are given of the mineral changes produced by 
fossilization, including that of the replacement of the original silica by calcic 
carbonate, which had been already noted by Pomel and Zittel. Siphonia is 
placed in the family Pachastrellide and the order Holorhaphidota, Carter. 
1877 Sontas, W. J. On Stauronema, a new genus of Fossil Hexactinellid 
Sponges, with a description of its two species S. Carteri and S. lobata 
(Ann. and Mag. Nat. Hist., 8. 4, vol. xix, pp. 1—25, Pls. I—V). 
Describes a fan-shaped Sponge with a very robust spicular mesh, the canals 
in which are stated to pass ordinarily from one node to another, and thus to 
differ from recent hexactinellids. The wall of the Sponge forms a thin, so- 
called oscular plate, which is overgrown at its base by a thick mass of irregu- 
lar spicular tissue. 
