20 
BRITISH FOSSIL SPONGES. 
108. 1871 Geritz, H. B. Die Seeschwiimme des unteren Quaders. Die See- 
109. 
110. 
eel 
Lie 
ee) 
schwiimme des mittleren und oberen Quaders (Palawontographica 
Bd. xx, 1 Th., pp. 1—41, Pls. 1—10). 
The identity of the minute structure of fossil Sponges with lattice-shaped 
mesh (Gitterschwiimme, A. Roemer) and recent hexactinellids is recognised, © 
and the fossil forms with this structure are placed in the same group with the 
recent. Fossil Sponges with the so-called vermiculate mesh are regarded as 
probably of the same nature as recent lithistid Sponges, and placed in the same 
group. The doubtful Spongites is placed under the Halisarcine. The classi- 
fication adopted by this author marks a great step in advance. <A mistake 
was made, however, in placing all Sponges with vermiculate fibres under the 
Lithistidee, simce many of them are calcisponges. 
1871 Hicks, H. Descriptions of New Species of Fossils from the Longmynd 
Rocks of St. David’s (Quart. Journ. Geol. Soc., vol. 27, p. 401, 
Pl. XVI, figs. 14—20). 
Describes some doubtful lines on rock surfaces as Protospongia (?) major 
and P. (?) flabella. 
1871 Putuurrs, J. Geology of Oxford and of the valley of the Thames. 
Gives a list of the Amorphozoa of the Cretaceous system, and figures some 
of the commoner Sponges from the Lower Greensand of Faringdon. 
1871 Carrer, H. J. On Fossil Sponge Spicules of the Greensand compared 
with those of existing species (Ann. and Mag. Nat. Hist., 4 S., 
vol. vii, pp. 112—141, Pls. VII—X). 
Very numerous forms of detached spicules from the Upper Greensand of 
Blackdown and Haldon are shown to correspond very closely with the spicules 
of recent tetractinellid, lithistid, and hexactinellid Sponges. 
. 1871 Smonowrrscu, 8. Beitriige zur Kenntniss der Bryozoen des Essener 
Griinsandes (Verh. d. nat. Ver. Jahrg., xxviii, 3 Folge, Bd. viii). 
Places as Bryozoa, Thalamopora cribrosa, Goldf., sp., and 7’. michelinii, n. 
(pp. 27—34, Pl. 1, I, 2), now shown to be calcisponges and included in 
Tremacystia, Hinde. 
1872 Harckxet, H. Die Kalkschwimme. 
The author denies the existence of entire fossil calcisponges and states that 
the forms generally known as such have no relation to the group. Further, 
states that the delicate character of recent calcisponges renders it impossible 
that similar forms can have been preserved in the fossil state, though it is 
not improbable that their detached spicules may yet be recognised. 
