CETOTOLITES. 535 
also manifests the Balenal character in the extension 
of the origin of the overarching wall around the mner 
end, throwing the opening of the tympanic cavity back- 
wards. 
In the account of these Cetotolites, read to the Geo- 
logical Society,* the vertical notch or indentation of the 
border of the involuted convexity of the tympanic bone 
of the Balena mysticetus is noticed in connection with that 
character in the Balena emarginata ; but in the Balena 
mysticetus, the involuted convexity does not swell out into 
lobes at the back part of the bone. 
Professor Henslow observes, “‘ It is not a little remark- 
able that all these specimens should have been procured 
within a very narrow compass, for I found none beyond 
the limits of two contiguous indentations in the cliff, a 
short distance to the north of Felixstow.”+ Mr. Rose, 
F.G.S., has, however, since discovered a fractured fossil 
tympanic bone of the Balana definita ma patch of crag, 
high up a rather lofty part of the bank of the river Orwell, 
ashort distance below Holywells, Suffolk. The dense tex- 
ture of this fossil, as of most of the specimens from Fe- 
lixstow, presented evidence of ferruginous infiltration in 
a dark layer surrounding the lighter-coloured central part 
of the bone. The long diameter of this specimen mea- 
sured three inches and a quarter, its short diameter two 
inches. 
* ¢ (Quarterly Journal of the Geological Society,’ No. I. p. 40. + Ibid. p. 36. 
+ Numerous other nodules, or pebbles, some cylindrical, some fusiform, with 
annular, or spiral, or longitudinal convolutions, occur in the Red Crag at Fe- 
lixstow, which present external indications of animal origin ; and yield, upon 
analysis, 56 per cent of phosphate of lime. They occasionally contain remains 
of small crabs and fishes, —sharks’ vertebrae, for example, like those of the 
London clay ; and they have been regarded by Professor Henslow, who first 
called attention to their probable origin, as coprolites. —‘ Proceedings of the 
Geological Society,’ December, 1843, p. 262. 
