CRUSTACEANS 



the typical Essex " spiders," as the members of the genus are always 

 found on a sandy or muddy bottom, to which the colour of the crabs 

 almost invariably corresponds.' After discussing some points in the 

 biology of Pisa gibbsii, without definitely stating that it is found in Essex, 

 he notes that ' Pisa tetraodon occurs at the Nore and may be considered 

 an Essex species.' Further on he says that ' the common shore-crab 

 (Carcinus maenas) is very widely distributed and is a well-known Essex 

 form, where its colour is invariably identical with the sandy or muddy 

 bottom on which the creature lives. When however we find it in rock- 

 pools on the granite or serpentine of Cornwall, or on the syenite or 

 basaltic shores of the Channel Islands, this interesting species assumes the 

 most beautiful markings, tinted with really gorgeous colour, and mottled 

 in the most delicate manner. It is often almost impossible to detect the 

 crab in these localities, so perfectly does it resemble its surroundings.' * 



Mr. Lovett's remarks on the colouring of the shore-crab are novel. 

 As a rule it is only young specimens that display any striking pattern, 

 the adults being in general of a sombre green or, as Leach says, * some- 

 times of a pale green more or less mottled with a darker teint [tint].' 1 

 Bell gives the colour as blackish green, with the qualification that ' they 

 vary, however, considerably both in the hue and in the intensity of the 

 colour,' * but this is very different from saying that they ever assume the 

 tints of sand and mud. 



The spider crabs no doubt owe their popular name to the long 

 spindly legs by which many of them show a kind of resemblance to some 

 spiders or to spider-like terrestrial animals. Science groups them in the 

 Oxyrrhyncha, the sharp-beaks, because they have the carapace acutely 

 produced in front. The readiness with which they utilize the resources 

 of the sea, its mud and sand, its weeds, its sponges, its zoophytes, and 

 other objects, for their own purposes of disguise, has long attracted 

 attention. Of late years the wonder has turned to admiration, from the 

 discovery that these crabs are not impassive sluggards, helplessly en- 

 cumbered and overgrown against their will, but active participants in all 

 that happens, each the predominant partner in a diversified yet strictly 

 limited company. On a territory consisting of their own crustaceous 

 covering they plant the garden, arrange the menagery, spread the soil, 

 permit the presence of fixed or moving tenants. By their arts of conceal- 

 ment, though they are pleasing to the palate of numerous and powerful 

 foes, they hold their place successfully in the battle of life. Their move- 

 ments are in general lethargic, but the long claws can be darted out with 

 lightning rapidity to seize the passing prey. 



To Mr. Lovett's notice of Stenorhynchus rostratus, Mr. William Cole, 

 F.L.S., the editor of the Essex Naturalist, adds the remark that it is also 

 found in the estuary of the Colne. On this same species Dr. H. C. 

 Sorby, LL.D., F.R.S., in manuscript notes on the Crustacea of this 



1 The Enex Naturafiit, vol. xi. pp. 252, 253 (1900). 

 1 MalMoitraca PoJofhthalmata Britaimur, text to pi. J (1816). 

 1 Brituh Sulk-eyed Cnutacea, p. 77 (1853). 

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