A HISTORY OF NORFOLK from the neighbouring sea. But the canny fishermen may have received dead specimens from a passing vessel, or the species may really have been the North American Limulus polyphemus (Linn.), which is caught by the million on the shores of the United States. Limulus, by the great size of its representatives, seems to deserve its name of king-crab, but, unfortu- nately for the name, it is not a crab at all. According to one set of disputants in a lively controversy, it is not even a crustacean, but an arachnid. Interesting as it is in itself, we must therefore reluctantly leave it alone, and pursue a humbler theme. Of Mr. Palmer's twofold statement that shrimps, meaning the edible shrimps of this country, are the least but most delicious of all shell-fish, the first part, that they are the least, is too untenable to need discussion ; the second part, that they are the most delicious, is a question of taste. Some men prefer oysters. But oysters have at least this advantage, that they really are shell-fish. Shrimps are not so, unless we please to follow dictionaries and Acts of Parliament in a defunct classification which mixes up crustaceans with molluscs. Shrimp itself is a vague expression, in- definitely defined by Webster as ' a long-tailed decapod crustacean of the genus Crangon, and others ; often applied to most of the smaller macrou- rans.' Probably Palmer refers to the widely diffused and extensively consumed Crangon vulgaris (Linn.), the 'common shrimp.' With this is sometimes found the Crangon allmanni (Kinahan), which can be distin- guished by the longitudinal groove on the back of the penultimate segment of the pleon, continued in shallower form on the terminal segment or telson. Because of this groove it is called by Adam White the ' channel-tailed shrimp.' Metzger records it from twelve fathoms on the Norfolk coast.^ It is so like its ' vulgar ' relation that often no doubt it passes under the eyes and palate of the unobservant as though it were itself a common shrimp. The tribe Caridea, to which shrimps and prawns collectively belong, is distributed into several divisions and numerous families. As of shrimps, so of prawns, there are numerous species and genera. The serrate sword projecting from the head is a fairly good mark of such prawns as are likely to be met with at English tables. Compared with the prawns of the whole world, those of England form an insignificant group, but they are not confined to a single species, nor even to a single genus. From various notices one is led to infer that Leander serratus, ' the common prawn,' is in Norfolk less common than Pandalus montagui (Leach), sometimes less correctly called Pandalus annulicornis. This has rings of red and white alternating on its antennas, and White gives its name in English, without much regard to euphony, as the ringed-horned prawn.* Leach, in 1815, writes : ' It is used at Yarmouth as an article of food, and is at that place so much esteemed for the table as to afford constant em- ployment during the summer season to several fishermen, who take it in abundance at a considerable distance from the shore, and name it from that
- Nordseefahrt der Pommerania, p. 29O.
^ Popular History 0/ British Crustacea, p. 126. 188
