Food of Oceanic Animals

Abstract

UNDER the above head, in a note which appeared in NATURE of the 16th Dec. p. 192, Mr. Gwyn Jeffreys “calls the attention of physiologists to the fact that plant-life appears to be absent in the ocean, with the exception of a comparatively narrow fringe, known as the littoral and laminarian zones, which girds the coasts, and of the ‘Sargasso’ tract in the Gulf of Mexico.” He then proceeds to say that, “during the recent exploration in H.M.S. Porcupine of part of the North Atlantic, he could not detect the slightest trace of any vegetable organism at a greater depth than fifteen fathoms. Animal organisms of all kinds and sizes, living and dead, were everywhere abundant, from the surface to the bottom … some of them being zoophagons, others sarcophagons, none phytophagons.” And, lastly, after asking “whence do oceanic animals get that supply of carbon which terrestrial and littoral or shallow-water animals derive, directly or indirectly, from plants?” and “can any class of marine animals assimilate the carbon contained in the sea, as plants assimilate the carbon contained in the air?” Mr. Jeffreys sums up his conclusions on the subject in the following words:—“At all events, the usual theory, that all animals ultimately depend for their nourishment on vegetable life, seems not to be applicable to the main ocean, and consequently not to one-half (sic) of the earth's surface.”