much importance as sources of food supply for fishes, are the larval 
forms of crabs, worms, barnacles and acorn-shells which often occur 
in enormous numbers. In still greater quantity, though much 
more minute are frequently found the two infusorian animals 
Ceratium tripos and C. frniis , and the curious little creatures 
known as arrow worms. The almost constant absence, on our 
coast, of floating vegetable life is, however, very remarkable when 
wo consider the profuse distribution of the smaller unicellular 
algaq not only in the warmer tropical seas, hut also even near the 
poles. Depending, as all animals ultimately must, upon plants for 
their existence, there can ho no doubt that when this minute vegeta- 
tion exists abundantly, the capacity of the water to support animal 
life must be greatly increased, and one is ready to think that if we 
could induce the German Ocean to become a nursery for diatoms, 
we should do more than all the hatcheries to increase the fish 
population. 
In connection with this subject, it is worth notice that in the 
neighbourhood of the Tyne and Wear considerable change appears 
to have taken place of late years in the vegetation of the littoral 
and laminarian zones — i.e. between, and for some distance beyond, 
tide marks. Thirty to fifty years ago the quantity of “ wrack ” 
washed up in these districts after a storm used to be very much 
greater than now. This must arise from the destruction of the 
ground on which the marine forests with their attendant animal 
life used to thrive. Several causes have probably been concerned 
in the destruction ; — first, the extension of piers and harbour- 
works of various kinds which not only may themselves occupy pre- 
viously productive areas, but by alteration of currents may silt up 
or scour them away ; secondly, the influx of sewage which renders 
the water unfit for most kinds of animal and vegetable life, and 
lastly, the discharge of refuse from steamships and the hoppers of 
the river commissioners. The fact of the decrease of “ wrack ” 
after storms is, at any rate, undoubted, and I think it is equally 
certain that round the mouths of the Tyne and Wear, as far at 
least as Whitley on the north and Ryhope on the south, the littoral 
fauna has become very much impoverished. Many forms of life 
which, half a century ago used to be common are now to be found 
only sparsely or not at all. This state of things can scarcely be 
without an influence on the abundance and well-being of such fishes 
as, in the earlier periods of their lives, have to seek the waters of 
the shore. 
