SEELET — Oil CHALK GASTEROPODS. 
89 
Fig. 19. Cristellaria Italica^ Defrance (D'Orbigny's Modeles,* 
nos. 19 and 85). This is not an uncommon form where Cristel- 
lariae abound, either in the recent or the fossil state. 
Besides the foregoing, we have seen Trochammina incerta, D'Orb., 
among the specimens from the Hampstead well, in Mr. Wetherell's 
collection. 
The London Clay from Wimbledon Common was got at about 100 
feet in a well-boring. That from Chelsea came from the foundations 
of the Battersea Park Bridge. 
The Foraminifera of the London Clay indicate a depth of about 
100 fathoms for the sea, in which it was deposited in this district. 
The accompanying Table shows the Foraminifera that we have re- 
cognized in the London Clay, arranged according to the classification 
proposed by Dr. Carpenter in his ' Introduction to the Study of 
Foraminifera,' 1862. The asterisk indicates their presence merely 
(the relative abundance not being known) ; their frequency and con- 
dition are shown in some of the columns by the following letters : — 
rc. rather common; c. common; rr. rather rare; r. rare; vr. very 
rare; vs. very small; s. small; rs. rather small; m. middle-sized; rl. 
rather large ; I. large. In some instances two very closely related, 
but still notable, varieties are mentioned together. 
CUTTINGS FHOM A NOTE-BOOK ON CHALK 
GASTEROPODS. 
By Harry See ley, F.G.S. 
Two years ago, collecting matter for future use, in travelling over 
the Chalk-lands, I made, in the museums visited, such brief memo- 
randa of striking fossils as might save the trouble of comparison with 
other specimens. The notes were never intended for publication in 
their present form, but as any more extended work on the subject is 
at present impossible, such <Df them as I have permission to print 
may be found useful to others engaged on similar work. 
This series is part of the magnificent collection in the Brighton 
Museum ; to the Committee of which I am indebted for the oppor- 
tunity of making use of them. 
Ceeithium ornatissimum, va7\ 
Conical, twice as high as wide. Many-whorled; whorls flat and narrow, being four 
times as wide as high. Each whorl is ornamented on the upper and lower sutural 
margins by a very numerous row of closely-placed tubercles. The anterior row has the 
tubercles elongated longitudinaUy ; those of the posterior row are more bead-like. Con- 
necting these rows are half as many a gain narrow, sharp, upright ribs. The tubercles 
* A set of these can be seen in the British Museum. 
YOL. VII. ' ^ 
