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THE ESSEX NATURALIST
Class PYCNOGONIDA
Nymphonidae
Members of the genus Nymphon commonly occur amongst
hydroids. Three species have been identified but their relative
abundance and distribution have not been fully established.
Nymphon gracile Leach
Nymphon rubrum Hodge
Nymphon brevirostre Hodge
Phoxichilidiidae
Phoxichilidium femoratum (Rathke)
Occasional records from the benthos.
Ammotheidae
Ammothea echinata (Hodge)
Very common on hydroids, on clean shelly bottoms in sheltered
positions such as creeks.
Pycnogonidae
Pycnogonum littorale (Strom)
Common in association with actiniarians in the benthos. In
1964 and 1965 the species became numerous with the increase of
actiniarians on the warm water discharge side of the Barrier Wall
at Bradwell.
Sub-Phylum INSECTA
Class APTERYGOTA
Order Collembola
Anurida maritima Laboulbene
On the surface of the water and among the plants in saltings
and on the seaweeds on the shore. Very common.
Phylum MOLLUSCA
Class LORICATA
Order Lepidopleurida
Lepidopleuridae
Lepidopleurus asellus (Gmelin)
Found in the Blackwater seawards of Osea Island and offshore
on clean shelly or stony bottoms. It is always sub-littoral. Com-
mon in grab and dredge samples prior to 1963 but less common
since.
Lepidochitonidae
Lepidochitona cinereus (Linne)
Very common on shelly and stony ground on the middle and
lower shore and less common sub-littorally. It is found on stones
and among mussels, Mytilus edulis, in St. Lawrence Bay, off Mill