Chromosomes of Eniwetok Opisthobranchiates — Burch and Natarajan 
259 
morphology in respect to all other opistho- 
branchs so far studied. 
ACKNOWLEDGMENTS 
Grateful acknowledgment is made to the 
United States Atomic Energy Commission for 
supporting the study by the senior author at 
Eniwetok by providing travel funds, logistical 
support, and use of the facilities of the Eniwe- 
tok Marine Biological Laboratory. The coopera- 
tion of the U.S.A.E.C. Eniwetok Field Office 
and of Holmes and Narver, Inc. greatly facil- 
itated the field collecting. A note of gratitude 
is due Dr. I. Eugene Wallen, formerly with the 
U.S.A.E.C., Dr. Robert W. Hiatt, University of 
Hawaii, and Prof. Henry van der Schalie, Uni- 
versity of Michigan, for promoting these 
studies; to Dr. William H. Heard, Florida 
State University, for assistance while at Eniwe- 
tok; and to John L. Tottenham, Staff Artist, 
Museum of Zoology, University of Michigan, 
for preparing illustrations of the animals used 
in this study. 
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