Douglas et al.: Geographic variation in cranial morphology of Stenella longirosCns 



75 



separately for management purposes. In particular, a 

 growing base of information suggests giving special 

 attention to the spinners from the relatively uniform 

 area of the Pacific just to the west of the Mexican/ 

 Central American coast, and viewdng the pattern of 

 morphologic variation as being broadly concentric in 

 nature. 



Acknowledgments 



S.B. Reilly and A.E. Dizon reviewed the manuscript 

 and provided useful suggestions. We thank J. Gil- 

 patrick and J.V. Kashiwada for preparing and curating 

 some of the specimens, as well as assisting with prep- 

 aration of data for analysis. Computer programs and 

 assistance were provided by F.J. Rohlf, R.R. Sokal, and 

 M.A. Schene. Support for aspects of this research was 

 received by the University of Oklahoma through Con- 

 tract 79-ABC-00167 from the U.S. Department of 

 Commerce, National Oceanographic and Atmospheric 

 Administration, and Purchase Orders 84-ABA-02177 

 and 40JGNF0532 from the National Marine Fisheries 

 Service, Southwest Fisheries Science Center, La Jolla, 

 CA. The following individuals provided access to 

 museum specimens: S. Anderson, G.G. Musser, and 

 D. Russell (American Museum of Natural History, New 

 York, NY); M.C. Sheldrick (British Museum of Natural 

 History, Tring, United Kingdom); S. Bailey, L.C. Bin- 

 ford, and J. Schoenwald (California Academy of 

 Science, San Francisco, CA); P.J.H. van Bree (Instituut 

 voor Taxonomische Zoologie, University of Amster- 

 dam, Amsterdam, The Netherlands); D.R. Patten and 

 J.E. Heyning (Los Angeles County Museum of Natural 

 History, Los Angeles, CA); C.P. Lyman and M. Rutz- 

 moser (Museum of Comparative Zoology, Harvard 

 University, Cambridge, MA); W.Z. Lidicker Jr. 

 (Museum of Vertebrate Zoology, University of Califor- 

 nia, Berkeley, CA); C.G. van Zyll de Jong (Museum of 

 Natural Sciences, National Museum of Canada, Otta- 

 wa, Canada); J.G. Mead and C.W. Potter (National 

 Museum of Natural History, Washington D.C.); D.W. 

 Rice and A.A. Wolman (NOAA Northwest and Alaska 

 Fisheries Science Center, Seattle, WA); L.J. Hansen 

 (NOAA Southwest Fisheries Science Center, La Jolla, 

 CA); G.F. Mees (Rijksmuseum van Natuurlijke His- 

 toire, Leiden, The Netherlands); A. Rea (San Diego 

 Museum of Natural History, San Diego, CA); M.L. 

 Johnson and E. Kritzman (University of Puget Sound, 

 Tacoma, WA); and G.L. Worthen (Utah State Univer- 

 sity, Logan, UT). 



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