LOWER MIOCENE OF ENGLAND. 
245 
Lower Miocene shell; Corbula pimm (Fig. 158), a species 
common to the Upper Eocene clay of Barton; Cyrena semi- 
striata (Fig. 159), several Cerithia, and other shells peculiar 
to this series. 
Fig. 158. Fig. 159. 
Corbula pisum. Hempstead Beds, 
Isle of Wight. 
Cyrena semistriata. 
Hempstead Beds. 
2. Next below are fresh-water and estuary marls and car¬ 
bonaceous clays in the brackish-water portion of which are 
Fig. 160. Fio*. 161 . found abundantly Cerithium 
plicatiim^ Lam. (Fig. 160), C. 
elegans (Fig. 161 ), and C. tri- 
cinctum / also Missoa Chaste- 
Hi (Fig. 162), a very common 
Kleyn Spawen shell, and which 
occurs in each of the four sub¬ 
divisions of the Hempstead se¬ 
ries down to its base, where 
it passes into the Bembridge 
beds. In the fresh-water por¬ 
tion of the same beds Pahidma 
Cerithium pUcatum, Cerithium elegans. lenta (Fig. 163) OCCUrS ; a shell 
Lam., Hempstead. Hempstead. identified by SOme COncholo- 
gists with a species now living, P. unicolor ; also several 
species of Lymneus., Planorbis.^ and TInio. 
Fig. 162. 
Fig. 163. 
3. The next series, or mid¬ 
dle fresh-water and estuary 
marls, are distinguished by the 
presence of Melania fasciata^ 
PaludinOj lenta.^ and clays with 
Gypris ; the lowest bed con¬ 
tains Cyrena semistriata (Fig. 
159), mingled with Cerithia and 
a Panopcea. 
4. The lower fresh-water and estuary marls cout^m Mela¬ 
nia costata.^ Sow., Melanopsis.^ etc. The bottom bed is car¬ 
bonaceous, and called the ‘‘Black band,” in which Pissoa 
Chastelii (Fig. 162), before alluded to, is common. This bed 
contains a niixture of Hempstead shells with those of the 
underlying Upper Eocene or Bembridge series. The mam- 
Rissoa Chastelii, Nyst, 
Sp. Hempstead, Isle 
of Wight. 
Paludina lenta. 
Hempstead 
Bed. 
