74 PROCEEDINGS OF THE NATIONAL MUSEUM vol. ne 



remaining 666 counts are from the literature or were supplied by 

 colleagues. The 1524 specimens pertain to 70 of the approximately 

 80 genera of sharks and to 135 of the approximately 300 species. 

 Because our purpose has been to survey', our coverage within in- 

 dividual species is far from complete, but considerable attention has 

 been paid to a few species that have presented problems. 



We wish to express our gratitude to the officials of the following 

 institutions for their assistance in providing specimens and X-ray 

 facilities. 



ANSP — Academy of Natural Sciences of Philadelphia 



BMNH — British Museum (Natural History), London 



CAS — Cahfornia Academy of Sciences, San Francisco 



CM — Canterbury Museum, Christchurch, New Zealand 



CNHM — Cliicago Natural History Museum 



DMNZ — Dominion Museum, Wellington, New Zealand 



GVF — George Vanderbilt Foundation, Stanford University, California 



IRSN — Institut Royal des Sciences Naturelles de Belgique, Brussels 



ISZZ — Institut fiir Spezielle Zoologie und Zoologisches Museum, BerUn 



MCSN — Museo Civico di Storia Naturale, Genoa, Italy 



MCZ — Museum of Comparative Zoology, Harvard University, Cambridge, 



Massachusetts 

 RNH — Rijksmuseum van Natuurlijke Historic, Leiden, Holland 

 SIO — Scripps Institution of Oceanography, La Jolla, California 

 SU — Division of Systematic Biology, Stanford University, California 

 TGFC — Texas Game and Fish Commission Marine Laboratory-, Rockport 

 UBC — University of British Columbia, Vancouver 



UMML — University of Miami Institute of Marine Sciences, Miami, Florida 

 UMMZ — University of Michigan Museum of Zoology, Ann Arbor 

 USNM — United States National Museum, Wasliing-ton, D.C. 

 UZMK — Universitetets Zoologiske Museum, Copenhagen, Denmark 



J. G. Casey, Bureau of Sport Fisheries, Sandy Hook Marine Labora- 

 tory, kindly provided some vertebral counts of Alopias superciliosus 

 and Isurus oxyrinchus, and H. Heyamoto, Bureau of Commercial 

 Fisheries, Seattle, Washington, sent us ten specimens of Sgualus 

 acanthias taken from off the coast of Washington. W. I. Follett of 

 the California Academy of Sciences, San Francisco, generously allowed 

 us to use his and J. D. Hopkirk's vertebral counts of Cetorhinus maxi- 

 mus and Carcharodon carcharias. These counts were made on verte- 

 bral columns in the CAS collections. We are grateful to Sheldon 

 Applegate, formerly of Duke University, for providing us with counts 

 from New Jersey and Delaware specimens of Carcharias taurus, and 

 to Elvira Siccardi, Faculty of Natural Sciences of Buenos Aires, 

 Argentina, for counts on Isurus oxyrinchus, Carcharodon carcharias, 

 and Lamna nasu^. 



Our identifications of the species of Sphyrna are the result of un- 

 published studies by Dr. Carter R. Gilbert, to whom we extend our 

 appreciation for allowing us to use his characterizations. 



