F. CHAPMAN-OSTRACODA FROM HITCHIN. 
61 
Family Cyprididje. 
Cyclocypris Iccvis (0. F. Muller).—This species is fairly common 
in the fresh-water bed of Hitchin. It is a common form in this 
country in fresh and brackish water. 
Cyclocypris globosa (Gr. 0. Sars).—The discovery of this species 
in the Hitchin deposits is of much interest, for it is quite 
a northern species, having been recorded from fossil deposits in 
Scotland; and as a recent form it is still found living in the locks 
and pools of the border counties of England, in Scotland, and in 
Norway. It is by no means uncommon at Hitchin. 
Scottia Browniana (Jones).—This is also a northern species. 
Mr. T. Scott found it living in pools in the island of Bute. It was 
found fossil at Clacton, Essex, by Professor Rupert Jones, and has 
since been recorded by him from Hitchin and from Sidestrand, 
Suffolk, and Chesilton, Dorset. 
Cypris virens (Jurine).—A common and widely-distributed form, 
and as a recent species inhabiting “ grassy pools and ditches which 
dry up in summer ” (Brady and Norman). Only one valve was 
found in the marl from Hitchin. 
Erpetocypris reptans (Baird).—This is a common British species, 
and its European distribution is wide. As a fossil it has been 
found in strata as old as the Weybourn Crag. At Hitchin it is 
common and often of large size, some of the valves measuring as 
much as 3*3 millimetres in length. 
Pionocypris vidua (0. F. Miillei').—This species has been found 
as a post-Tertiary fossil in the Fen district, and it is common as 
a fresh-water form in England and Europe generally. At Hitchin 
it is not uncommon. 
Ilyocypris gibba (Ramdohr). — This species, well known as 
a recent form, is also known from the Hamstead beds (Oligocene) 
of the Isle of Wight, and it is common as a post-Tertiary fossil in 
England and Scotland. At Hitchin only one well-differentiated 
specimen was found, and in this the principal tubercle is prominent 
and recurved. 
Ilyocypris Bradii , G. 0. Sars. — The commoner form of this 
genus in the Hitchin deposit appears to be the non-tuherculate 
type defined by Sars under the above name, of which three valves 
were found. 
Candona pubescens (Koch).—This is a common species in the 
living condition. As a post-Tertiary fossil it has been recorded 
from Whittlesea, the valley-drift near Salisbury, the old land-drift 
at Chesilton, Portland, the gravels at Barnwell near Cambridge, 
and from Hitchin, where well-formed valves are found, but they 
are not very common. There are also present several valves of 
the form usually described under the name of C. albicans , but now 
thought to he only the young of C. pubescens . 
Candona lactea , Baird.—This common fresh-water species, which 
is well known from numerous post-Tertiary deposits, is very 
common at Hitchin. 
