52 Papers from the Department of Marine Biology. 
ing for records for the different islands, but no doubt scattered records 
have been overlooked, while many in which I have lacked confidence 
are ignored. 
The purpose of this investigation and report is to see if the dis- 
tribution of these very littoral species throws any light on the faunistic 
relations of the various islands. But it should be understood at the 
start that we have nowhere nearly enough data on which to base any 
important conclusions. Thus, while the littoral echinoderms of Florida 
and the Tortugas are quite completely known and those of Jamaica 
are almost equally well listed, our knowledge of the Cuban fauna is, 
in this group, very incomplete and nothing whatever is known of the 
Isle of Pines or of the Cayman Islands. Of the echinoderms occurring 
on the shores of Porto Rico and the United States Virgin Islands, we 
are fairly well cognizant, but passing eastward and southward we enter 
a region of which our knowledge is most superficial until Barbados and 
Tobago are reached. This report is therefore merely introductory to 
the subject, but it is hoped that it may serve as a useful beginning. 
One word is necessary as to the geographical limits of the region 
here designated as ‘‘West Indies.’”’ It extends from Bermuda on the 
north and the Tortugas on the west to Tobago in the southeast. Per- 
haps, strictly speaking, these three extremes do not belong in the 
region at all, but as their littoral faunas are exceptionally well known 
it would be absurd to leave them out of account. 
In concluding this introduction, I wish to express my thanks to those 
whose encouragement and aid have made my work possible. I desire 
particularly to record my great and lasting obligations to the late 
Professor William Keith Brooks, of the Johns Hopkins University, 
who first opened to me the fascinating field of marine zodlogy; to 
the late Dr. Alexander Agassiz and to Mr. Samuel Henshaw, of the 
Museum of Comparative Zoédlogy; and to Dr. Alfred G. Mayor of 
the Carnegie Institution. At Tobago I had the privilege of the 
constant companionship and help of my honored colleague, Dr. Th. 
Mortensen, of Copenhagen; it is a pleasure to acknowledge here my 
debt to him. Another colleague, Dr. W. K. Fisher, of Leland Stanford 
Junior University, has put me under obligation by permitting me the 
use of certain field notes made by him during the summer of 1918 
at Barbados and Antigua, where he was a member of the party sent 
out by the University of Iowa, under Professor C. C. Nutting. I am 
glad to thank Professor Nutting and Dr. Fisher for permitting me to 
use these notes. 
There are many to whom my thanks are due for help in collecting, 
but I forbear attempting to name them. I must, however, offer my 
particular thanks to Mr. John W. Mills, chief engineer of the Tortugas 
laboratory, whose interest and help have been invaluable. 
