42 SCIENTIFIC SURVEY OF NORWICH AND DISTRICT 
Annelida.—Practically all our knowledge of the earthworms of Norfolk 
is due to the work done upon the group by Mr. A. Mayfield. The 
study was further taken up by the Rev. Hilderic Friend, whose paper 
in Trans. N. N. Nat. Soc., vol. ix, part 3, pp. 394-405, upon ‘ Some 
Norfolk Annelids ’ (with special reference to Sutton Broad) should 
be consulted ; he records some 38 species. Among other Polycheta 
may be mentioned Nereis diversicolor, abundant in Breydon and other 
estuarine habitats ; Aphrodite aculeata, the sea mouse, is not uncommon 
on the coast ; Arenicola marina (lugworm) is dug for bait in a few places, 
e.g. Blakeney ; Lanice conchilega builds its tubes in the sand at Yarmouth, 
Sheringham, etc. ; Pectinaria korenii is occasionally washed ashore in large 
quantities. 
Hirudinea irene the leeches Hemopis sanguisuga, Herpobdella 
atomaria, Glossosiphonia companulata, and doubtless others occur 
commonly in Norfolk waters. 
ARTHROPODA, 
Crustacea —With the exception of records due to a German explora- 
tion of the North Sea carried out about three- -quarters of a century ago 
on the ss. Pommerania, and scattered references in works on British 
Entomostraca, little fresh material had been published on the Crustacea 
of Norfolk prior to 1904. For Marine Crustacea conditions are not very 
favourable ; although the county has a lengthy coastline there is an 
absence of sheltering inlets which foster many aquatic invertebrates ; the 
temperature of the water too is subject to considerable fluctuation. 
Crab and lobster fisheries are carried on at Cromer, Sheringham, 
Runton, and Weybourne, where large flint boulders upon a bed of marl 
with a vast forest of seaweed form a splendid feeding place for the edible 
crab. ‘They are taken in pots set out to sea from the foreshore to a distance 
of two miles ; the fishing grounds cover an area of about sixteen square 
miles. 
The most recent work upon the Marine Crustacea was carried out in 
the region around Blakeney Point by T. J. Hart, and the following brief 
notes are taken from his paper ‘ Notes on the Crustacea Malacostrata’ 
in the area mentioned (Trans. N. N. Nat. Soc., 1929-1930). 
Decapoda.—Cancer pagurus (edible crab) chiefly frequents inshore 
during ecdysis. Carcinas menas: these shore crabs or ‘ ghillies’ to 
give them their local name, are present in enormous numbers in the salt 
marsh creeks, and although they are useful scavengers, they are a nusiance 
to line fishers as they take the bait meant for their betters. Portunus 
depurator : the cast shells of this commonest British swimming crab are 
frequently cast up on the beach. Eupagurus bernhardus (hermit crab) 
is fairly common. Homarus vulgaris (lobster) occasionally shelters in 
holes and corners in wrecks. Leander serratus (common prawn) is found 
in tide pools, but L. squilla, the ‘ white prawn’ is not so common. 
Hippolyte varians is widely distributed in tidal pools and Crangon vulgaris 
(common shrimp) is abundant upon the sandy bottoms of tidal creeks. 
Among the Amphipoda are listed: Gammarus locusta, common under 
stones ; Orchestia littorea among stones and piles at Morston ; Callopius 
0) 
