PREFACE. 
The present report, intended primarily as a contribution to zoédgeography, 
has been made possible through the opportunity given me as a member of the 
Expedition of the Carnegie Institution of Washington to Torres Strait in 1913. 
Every possible facility was afforded for studying the littoral echinoderms, not 
only at Mer, the largest of the Murray Islands, where a laboratory was maintained 
for five weeks, but also at Green Island near Cairns in northern Queensland, at 
Thursday Island, at Erub (Darnley Island), and at Badu (Mulgrave Island). These 
brief glimpses of the reef life at widely scattered points were invaluable in acquaint- 
ing me with the Torres Strait fauna, but it must not be supposed that they were 
adequate to give a satisfactory knowledge of its distribution. They merely served 
to show that local conditions may play a large part in the distribution of species 
and to make one cautious in drawing conclusions from observations so hastily made. 
Besides its primary purpose, this report is offered as a contribution to our 
knowledge of echinoderms, particularly their natural history and taxonomy. Wher- 
ever a species has been observed in life by me, I have given all the data I could 
secure regarding its occurrence and habits. Oftentimes, of course, when species 
were taken but once or at best very rarely, these data amount to little, but they 
may perhaps be suggestive. As for the taxonomy, the new species of crinoids with 
which I met have already been described ! and it has not seemed desirable to repeat 
the original descriptions, but figures of these new forms are given herewith for the 
first time. So, too, the new ophiurans have been described and figured by photo- 
graph,” but colored figures of some of the most notable species are given in the 
present report. No new echini were found by the Carnegie Institution’s party. 
The new asteroids and holothurians are here described and figured for the first time. 
In view of the fact that the local use of this memoir will be infrequent and 
small, it has not seemed desirable to give artificial keys to all the species. Instead 
of this I have taken occasion to make revisions of certain genera or families which 
are unusually well represented in the Torres Strait region and it is hoped that these 
will be of service to students of echinoderms, quite regardless of the narrow geo- 
graphical limits to which this report is confined. 
It would be most ungracious if I failed to express in this brief introduction 
my gratitude to those whose assistance has made the present work possible. To 
Dr. Alfred Goldsborough Mayor, Director of the Department of Marine Biology 
of the Carnegie Institution of Washington, I owe thanks not merely for the oppor- 
tunity of visiting Torres Strait and enjoying the privileges of the laboratory at Mer, 
but for his unfailing interest in my work and his determination that nothing he 
could do should be left undone to make that work successful. No words could 
adequately express my appreciation of what I owe to him, but even these few lines 
1See H. L. Clark, 1915. Comatulids of Torres Strait. Carnegie Inst. Wash. Pub. No. 212, pp. 97-125. 
2 See H. L. Clark, 1915. Catalogue of Recent Ophiurans. Mem. M. C. Z., 25, pp. 163-376, plates 1-20. 
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