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by this fossil, and, equally so on the coast, by the presence of 
Echinoconus conicus. Whenever you find it you may be 
certain you are near Marsupites, at least, on the coast. Lima 
hopert is found of a large and fine form, but, owing to the 
delicacy of the shell, difficult to separate from the matrix. 
Spondylus spinosus here attains its maximum size. They are 
quite common, wih the spines well preserved, but are very 
fragile, and great care is required in cleaning. If the chalk is 
allowed to dry, the spines are more easily saved. Ostrea 
wegmanniana (D’Orbigny) was discovered, for the first time in 
England, in 1899, in this zone, by the writer. The original and 
finest block, for they are gregarious, is among the collection to 
illustrate this paper. It ranges from the Uintacrinus beds at the 
Black Rock to the base of the Actinocamax (Belemnitella) 
quadratus zone, near Rottingdean. The most likely place to 
find specimens is in the inter-tidal chalk, one hundred yards east 
of the Pumping Station. They are well known in the chalk of 
France and were found many years ago by Mr. Griffith and 
Dr. Rowe, but not identified by the Geological Survey, Jermyn 
Street. This zone has only one Ammonite, and a very remark- 
able one it is (Amuinonites leptophyllus), popularly known as 
Landscapes, a good description of their sutures, and sometimes 
Carpet Slippers, which is not so appropriate. It goes from 
Uintacrinus to the middle of the Actinocamax zone beyond 
Rottingdean. There is a fair specimen at present exposed on 
the inter-tidal chalk near Roedean Cottage, 4 feet 3 inches in 
diameter, in circumference 12 feet 9 inches. They are quite 
common, but generally much worn. They are not found in 
France. This is an interesting fossil, the last species of the 
race, and it is curious how it should have become extinct on 
attaining this enormous size. There is no evidence from the 
chalk structure to exhibit any violent change in the condition of 
life to suddenly destroy this genus, which survived numerous 
and sudden changes throughout the Lias, passing above the 
Gault, in very different conditions to the chalk, in diminishing 
numbers, and finally disappears in the Actinocamax (Bel.) 
quadratus zone, long before the chalk deposits ceased to be laid 
down. There is a fine specimen in the British Museum, taken 
from the neighbourhood of Rottingdean. Cyphosoma kenigi, 
one of the beautiful fossils of the zone, is fairly common in 
fragments, but specimens in good condition are rare. 
The lower part of the zone, marked No. 4 on the 
diagram, is the sub-zone of Uintacrinus. This fossil was a 
free swimming crinoid. The first specimens were collected by 
Professor Marsh in 1870, from the Uintah Mountain, hence 
the name. A fine block from Kansas in the British Museum, 
with perfect specimens, led to a search in this country, with 
the curious result that plates and ossicles were found in Dr. 
