INTRODUCTION. 5 
research. Moreover, association, if not the sole 
creator, is at least a most important factor of 
the beautiful; and therefore the sight of one of 
these animals is now much more to me, in the 
respects which we are considering, than it can be 
to any one in whose memory it is not connected 
with many days of that purest form of enjoy- 
ment which can only be experienced in the pursuit 
of science. 
And here I may observe that the worker in 
marine zoology has one great advantage over his 
other scientific brethren. Apart from the intrinsic 
beauty of most of the creatures with which he has 
to deal, all the accompaniments of his work are 
zesthetic, and removed from those more or less 
offensive features which are so often necessarily 
incidental to the study of anatomy and physiology 
in the higher animals. When, for instance, I con- 
trast my own work in a town laboratory on 
vertebrated animals with that which I am now 
about to describe upon the invertebrated in a 
laboratory set up upon the sea-beach, it is im- 
possible not to feel that the contrast in point of 
enjoyment is considerable. In the latter case, a 
summer’s work resembles the pleasure-making of a 
picnic prolonged for months, with the sense of feel- 
ing all the while that no time is being profitlessly 
spent. Whether one is sailing about upon the 
sunny sea, fishing with muslin nets for the surface 
fauna, or steaming away far from shore to dredge 
for other material, or, again, carrying on observations 
in the cool sea-water tanks and bell-jars of a neat 
