Bulletin of the Museum of Comparative Zoology 
AT HARVARD COLLEGE. 
VoL. XXXII. No. 5. 
REPORTS ON THE DREDGING OPERATIONS OFF THE WEST COAST OF 
CENTRAL AMERICA TO THE GALAPAGOS, TO THE WEST COAST 
OF MEXICO, AND IN THE GULF OF CALIFORNIA, IN CHARGE OF 
ALEXANDER AGASSIZ, CARRIED ON BY THE U. S. FISH COMMIS- 
SION STEAMER “ALBATROSS,” DURING 1891, LIEUT. COMMANDER 
Z. L. TANNER, U. S. N., COMMANDING. 
XXIII. 
PRELIMINARY REPORT ON THE ECHINI. 
By ALEXANDER AGASSIZ. 
{Published by Permission of MARSHALL McDONALD and GEORGE M, BOWERS, 
U.S. Fish Commissioners. ] 
Witn THirtTEEN PLATES, 
AND A CHART OF THE ROUTE OF THE “ALBATROSS.” 
CAMBRIDGE, MASS., U.S. A. : 
PRINTED FOR THE MUSEUM. 
Jung, 1898. 
