2 
INTRODUCTION. 
in autumn by the jellies of the medusa?, the storms of winter 
and spring wholly alter the aspect. Immense banks of sea¬ 
weeds mingled with black fragments of wood, coal, and 
muddy matter cover the beach, which in many parts becomes 
brilliantly phosphorescent at night from the zoophytes and 
annelids on the blades of the tangles. Amidst this debris are 
vast numbers of sponges, zoophytes, shells, starfishes, annelids, 
crabs, and fishes which have been swept from their various 
habitats. All storms are not equally prolific; they also vary 
in regard to the abundance of the several groups—a feature 
probably due to the direction of the wind and the invasion of 
particular sites. The waste of marine life in such storms does 
not attract much notice; yet it is extraordinary and so constant 
that it may be regarded to some extent as a check upon its 
uninterrupted development. It is, however, to be remembered 
that even the autumnal ripple in the Outer Hebrides brings 
countless swarms of Salpce , Velellce, Medusce } and other forms 
to die on the beach. 
When the tide has receded after a severe storm the general 
appearance (to select an example in October) is as follows :— 
Besides the Fuci and other seaweeds, here and there banks 
are formed almost entirely of tangles. Now and then one is 
attached to the shell of a living dog whelk, a cumbrous load 
for so tiny a mollusk; others spring from polished pebbles 
(bound together by their roots), from the shells of the great 
whelk, Tapes pullastr a ^Mactr a solida, horse mussels, and others, 
or bear evidence of having been forcibly torn from the rocks. 
The latter more readily happens when the surface of the rock 
has been coated with Balani , Lepralice , and the purplish dif¬ 
fused form of Gorallina officinalis , to which the roots of the 
tangles adhere—a fact which can be tested in a rock-pool. 
In the interstices of the twisted roots many specimens of Saxi- 
cava rugosa occur, their habitations being more easily con¬ 
structed, though less secure, than perforations in the rock 
itself. Porcelain crabs can scarcely be observed in greater 
abundance, in company with the young of the shore and 
spider crabs ; while a few sessile-eyed crustaceans try to escape 
notice in the crevices tenanted by common and brittle stars. 
The root-fibres also give shelter to specimens of dog whelks, 
