The Scottish Marine Station

Abstract

THE equipment of the Research Station at Granton, Edinburgh, has now been increased by the construction of a system of large tanks provided with a constant circulation of sea-water. These tanks are arranged very nearly according to the plan described in the account of the station and its work which was published in April last. The aquarium itself occupies the ground-floor of the building, whose upper story forms the biological laboratory, and it consists of seven large tanks, five of which are shallow, and two deep, the latter being provided with glass fronts. The pump, which is driven by a steam-engine, the high-level reservoir, and the low-level reservoirs are situated at other parts of the premises. One of the deep tanks is being used for the study of the still mysterious life-history of Myxine glutinosa. Last week nearly 150 specimens of that animal were brought alive to the station from the neighbourhood of St. Abb's Head, where it is very abundant. These were successfully domiciled in the aquarium. As out of three specimens brought alive to the “Ark” (the floating laboratory belonging to the station) on May 1, and kept in a small glass aquarium about 15 inches long and 9 inches broad, two are still alive and healthy, there is good reason to hope that there will be no difficulty in keeping a large number alive for any length of time in a tank about 7 feet by 5 feet by 4 feet, which are the dimensions of the one now used for the purpose. It was found in the former experiment that the Myxine when left to themselves, burrowed into the layer of mud which had been placed at the bottom of the small aquarium, and lay for hours motionless, their bodies, with the exception of the extreme tip of the snout, being entirely buried. The snout is protruded for the purpose of respiration, a current of water passing constantly through the nostril into the œsophagus, and escaping at the two respiratory apertures. The normal condition of the animal when not actively engaged in the search for food is evidently to lie thus buried in mud. It is well known to fishermen, at least to those who are employed in line-fishing, that eellets, as Myxine are called by them, are met with almost exclusively on muddy ground. At the place where the creatures are more abundant than anywhere else in the neighbourhood of the Firth of Forth, namely, off St. Abb's Head, the sea-bottom throughout an extensive area consists of soft black mud. A quantity of this mud was brought to the station with the living specimens, and a layer of it 6 or 8 inches in depth placed at the bottom of the tank in which the Myxine were to be kept. The animals are now thickly scattered through the layer of mud, like earthworms in garden soil.