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THE CRUSTACEA OF SUFFOLK.
THE CRUSTACEA OF SUFFOLK: CRABS,
LOBSTERS
AND
PART
I.
SHRIMPS.
and conspicuous animals are naturally those that first attract the Naturalist's attention ; and in Britain none, after the Vertebrates, are larger and, in the sea, more conspicuous than Crabs and Lobsters. Every child of enquiring mind is eager to know all about the denizens of wave-washed coasts and the rocks that so often fringe them : I myself was asking such questions in 1877, though on the south and not east coast of England. T h e profusion of kinds to be met with varies a good deal with the geology of the sea-line, for shelter is an essential attribute to the lives of these creatures and, if they do not possess the horsesense (which I deny them) of choosing a safe retreat from their legions of enemies, they must be exterminated despite extraordinary powers of reproduction. Shelter is afforded mainly by rocks, good hard stone interspersed with many fissures and crannies, wherein they can retreat to safety. Until quite recently our Suffolk shore has been regarded with no small scorn in this respect: a nearly straight line, bottomed by little but shifting sands, opening at a half-dozen points into estuaries, bottomed by nothing firmer than mud. Surely all self-respecting Crabs would elevate their (supposititious) noses at such a home ! But Neptune is remorseless ; he will have his waters inhabited and aptly hygiened. So Crabs were washed by some undertow from their fissures and crannies in the south-west, swept by ocean currents east and north tili dumped upon our coast. Off Bawdsey, indeed, they do find some apology for their erstwhile rocks in the indurated London Clay of the beach, coated by a thin sheet of Alga:; elsewhere all the Suffolk shore is simply sand, and shelter to be found solely around such extraneous objects as piers, breakwaters and foreign matter lying on the North Sea bed. LARGE
Both Crustacea and Tracheata belong to the Arthropoda and the former includes a large number of British species, though approaching to nothing like our fifteen thousand Insects of the ' a t t e r - Crustacea are primarily divided into Malacostraca and kntomostraca, such as the water-fleas (Phyllopoda and Ostracoda), into the Copepods comprising many Carp- and other lice, and into the well-known Barnacles (Cirrhipedia). Malacostraca consist, besides our stalk-eyed Crabs, Lobsters and Shrimps, of the sessile-eyed Amphipoda and Isopoda along with the bivaivesnelled Leptostraca. ^ ith this large mass of animals to deal with, it is well to present o n c e t}l e sole group of which our Suffolk knowledge is yet at adequate. Indeed, so ill-adapted is the character of our coast JE