SIR,—With reference to your article on this subject in your
issue of August 6th, the interesting feature of the Norway lobster consists in its character as an outlying colony of an exclusively Northern type, which has died out elsewhere in more Southern climes, but has retained an isolated footing from the Glacial period in congenial circumstances. As •to its habits and habitat, I may presume to offer some remarks which appear in a work I published some years ago :—*
"The Norway lobster, found in swarms locally distributed over the deepest parts of the northern and central portion of the Gulf of Quarnero (Fiume), must be considered a colony of an entirely foreign form, as it is not met with in any other part of the Adriatic (or Mediterranean ?) In its company appear other Boreal forms equally strange to the Mediterranean fauna, and altogether to the Lusitanian province. In order to account for he insular appearance of this association of Northern represen- tative forms, it is necessary to assume that, as elsewhere where analogous appearances of Boreal 'outliers' occur, these forms had a further Southern distribution during the Glacial period, and that in course of time, owing to a raised temperature of the waters, particularly in summer time, their distribution became limited to the deeper and cooler regions, as long as the nature of the bed proved suitable, and the pressure of the water was not too great. The Gulf of Fiume, the Quarnerolo, and the Channel of Punta Croce are depressions in the bed to which this theory applies. Further south they are shut in from the open sea by a ridge of higher ground, which accounts for their isolation, whilst the lower temperature which prevails on the bed of the Quarnero, and the difference in the composition of the water, due to the limestone springs, must explain why they prosper here, whereas they do not occur in the neighbouring Dalmatian waters.
According to Mr. R Godwin Austen (` The Natural History of the European Seas'), the Nephrops Norvegicus has its numerical maximum in, and is a good characteristic crustacean for, the Scandinavian region, but it occurs abundantly in Dublin Bay ; it has not, however, according to Mr. W. Thompson, a general distribution—such as west and south even throughout the Irish seas (nor has it in the Adriatic). ` We may feel sure, from its excellence as an edible species, that it has not been overlooked by fishermen, whilst its size, form, and propor- tions make it the most elegant crustacean we have, a prize to be valued by any naturalist ; yet, strange to say, it has not been recorded from the western coasts of France, nor do we meet it till we reach the Mediterranean. It seems to be abundant in the Adriatic, in which sea it may be noticed that several other " outlying " forms of northern types are also met with.' The writer is not aware of its appearance elsewhere in the Mediter- ranean. In the Gulf of Fiume it is found in depths varying from twenty to forty-five fathoms, on a bed consisting chiefly of loam or clay ; springs from the limestone rock below, influencing the degree of saltness and the temperature of the water ; change of temperature slow and difference between extremes 16-18 deg. F., maximum 62 deg. F., minimum 45 deg. F. ; pressure at thirty fathoms 6.35 atmospheres.
The Scampo (pl. Scampi), as the Norway lobster is called at Fiume, is caught by the Italian trawlers hailing from Chioggia, which are met with all along the Austrian shores of the Adriatic from September to May, and is at its best during the full moon, when specimens of eight to ten inches in length are not unusual. It holds the first place in the Fiume fish-market, and sells at ls. 6d. to 5s. per kilogramme according to size and season, the demand being enhanced at Easter and Christmas. It is sent to Trieste, Venice, and Vienna, where it is considered a great delicacy, the heads being removed before transit, and the tails fetching as much as 10s. per kilogramme. The months June- September are a close season by treaty.
Turning to the rock lobster (Palinurus vulg.) its habitat is different, and the two species do not occur together. The rock lobster is found in the medium declivity and depth ranging from ten to twenty fathoms, mostly on steep inclines, where sweet surface waters have no effect and submarine springs do not issue forth ' • average temperature 56 deg. F. It is caught in Dalmatia from May to August, especially off the islands of Lesina and Lissa ; near Rogosnica, Sebenico, as *ar as San Pietro, just south of the island of Lussin. It is not caught further north (the habitat of the Norway lobster). It is inferior as food to the lobster (Homarus vulg.) It is called Langusta, and is caught with a trammel-net, or in willow-basket-traps (Nasse, Verse), baited with sea-spiders, or sardines, &c., or by night with a prong in shallow water by artificial illumination. For illustrations and descriptions of the Norway and rock lobsters consult Professor T. H. Huxley's monograph, ' The Crayfish, an Introduction to the Study of Zoology,' London : Kagan Paul, 1880."
—I am, Sir, &c., G. L. FABER,
British Consulate, Fiume. Consul.
• "The Fisheries of the Adriatic, and the Fish thereof." By G. L. Faber, 11,13.14. Consul for Fiume. Loudon : B. Quaritch. 1881.