Table 8. — Range of total lengths and measurements expressed as percent of total length in Apristurus and Halaelurus 



A look at the literature on scyliorhinids of the 

 Indo- Pacific and an examination of very few speci- 

 mens suggests that studies of Indo-Pacific species 

 will provide a better basis for estimates of phylo- 

 genetic relationhips than can be made from At- 

 lantic species alone. The Atlantic material does 

 suggest, however, that more detailed study of den- 

 tition would be desirable, especially with attention 

 to tooth development. For this review no positive 

 evidence on scyliorhinid migration and very little 

 information on habit patterns were found. Fur- 

 ther studies of species found in the higher latitudes 

 off South America appear most promising for esti- 

 mating the course of scyliorhinid phylogeny. 



ACKNOWLEDGEMENTS 



Work on this paper was started in 1957 when 

 the intention was to describe a new species of 

 Scyliorhinus from the single specimen of that 

 species then known. An illustration of this 

 specimen was prepared at the time by Nancy 

 Mead and is used here. Additional material be- 

 came available later, requiring description of 

 other new species. Illustrations of several of 



these were prepared by Mildred Carrington. 

 With a decision to expand the paper to cover cat- 

 sharks of the western Atlantic region, other illus- 

 trations were prepared by Mary Wagner. 



Examinations of type material by Dr. Daniel 

 M. Cohen and radiographs prepared by staff tech- 

 nicians at the Bureau of Commercial Fisheries 

 Ichthyological Laboratory in Washington, D.C., 

 helped me reach an opinion on the status of Apris- 

 turus profwndorum (Goode and Bean). 



I am especially indebted to Finnur Gudmunds- 

 son, Director of the Museum of Natural History, 

 Reykjavik, for arranging the loan of Saemunds- 

 son's type of Scylliwm laurussomi, and to F. Wil- 

 liams, Director, Guinean Trawling Survey, for the 

 loan of specimens of scyliorhinids from the west, 

 coast of Africa. 



Photographs of Halaelurus bivius and H. chi- 

 lensis included in this paper were made by 

 Smithsonian Institution staff photographers. 

 One photograph of jaws of Apristurus riverl was 

 made by Ruth Ortman, and a photograph of tooth 

 arrangement in Pristiophtmis was made by staff 



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U.S. FISH AND WILDLIFE SERVICE 



