xliv 
INTEODUCTIOX. 
of the horizons of the species that had been recorded from the 
Farringdon Sponge Bed. The thirty -five species in his list identified 
from that bed are distributed among the following horizons : — 
Species. 
Danian 3 
Senoniau 9 
Turonian ... ... ... ... 1 
Cenomanian ... ... ... ... 10 
Albian 2 
Aptian ... ... ... ... 0 
Neocomian ... ... ... ... 9 
Bajocian I 
The age of the bed is generally regarded as Aptian,^ which is 
the only division from which no species was recorded. This list, 
however, does not prove that the Bryozoa are of no stratigraphical 
value ; it merely shows that the determination of the species had 
followed wrong lines. 
The Literature of Cretaceous Bryozo.\.^ 
The work on the British Cretaceous Bryozoa is remarkably 
scanty. A few species were poorly figured by pioneer paleon- 
tologists, as in Kbnig’s “ leones fossilium sectiles ” (1825), 
S. Woodward’s “ Geology of Norfolk ” (1833), and Mantell’s 
“ Medals of Creation ” (1844). The first British work of permanent 
value was by Lonsdale, who in 1845 described some Cretaceous 
Bryozoa from North America, and then in 1849, 1850, and 1851 
described, with perhaps excessive detail, a few species from the 
English Lower Greensand and from the Chalk of Sussex. 
In 1846 and 1850 Austen, subsequently known as Godwin- 
Austen, recorded a few Bryozoa from the Lower Greensand, and 
David Sharpe, in 1854, described a few species from the same 
horizon at Earringdon. Then followed an interval of twenty-six 
years, during which the only addition to the British Cretaceous 
Bryozoa that requires notice was the late Professor Seeley’s 
^ See, however, G. W. Lamplugh. “ Belemnites of the Farringdon ‘ Sponge 
Gravels’”: Geol. Mag. 1903, dec. iv. vol. x. pp. 32-4. He holds that the 
belief that many of the belemnites in these gravels are remanie is without 
adequate foundation, and assigns a pre- Aptian age to this deposit. He regards it 
as “probably equivalent to the lowermost portion of the Lower Greensand 
Series of south-eastern England.” 
2 Eeferences are given in the Bibliography, pp. 315 et sqq. 
