10 



FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 

 Table 1. — Tooth-row counts in carcharhinid sharks taken off Salerno, Fla., summer of 19^7 



* All counts made from cleaned jaws from whicii all membranous sheatliing had been removed to permit accurate counts whether or not teeth of the 

 functional row were missing. 



pectoral fin in adults than in young for E. ndl- 

 ierti, but an entirely diiferent condition in F. 

 longimanus. 



The sandbar sharks available to me were re- 

 markably uniform in general appearance and in 

 those features that I could measure, count, or 

 compare. In an attempt to learn something from 

 morphometries, a considerable number of milberti 

 and other species were measured carefully and in 

 detail. However, the principal value that I de- 

 rived from this excessively laborious task was in 

 the deliberate examination of specimens enforced 

 by measurement of detail and in the notes made 

 to accompany the measurements. The exercise 

 served also to impress upon me the difficulties 

 attending attempts to get adequate series to show 

 growth patterns among some of the species of 

 large sharks which are not only migratory but 

 probably short lived. 



A characteristic of great importance for field 

 recognition of specimens of carcharhinid sharks 

 is the total length of the specimen considered in 

 connection witli its .sex and maturity (fig. 3). 

 The mammalogists and ornithologists have long 

 considered total length important in identifica- 

 tion because mammals and birds have determi- 

 nate growth patterns. As will be shown later, 

 E. milherti has growth characteristics which re- 

 sult in adults of predictable size. Furthermore, 



the size range of adults within the known seg- 

 ments of the population falls within limits which 

 are narrow enough to facilitate field identifica- 

 tion by process of elimination. Thus, an adult 

 Eulamia more than 92 inches in total length is 

 probably not milberti, and adult males less than 

 70 inches or adult females less than 72 inches in 

 total length are unknown. 



DISTRIBUTION OF EULAMIA MILBERTI 



General nature of distribution 



The distribution of Eulamia milberti is diffi- 

 cult to treat adequately because, even though 

 further discussions will be limited to the popula- 

 tion of the western North Atlantic, the distribu- 

 tion patterns are extremely complex. The adults 

 segregate by sex and to some degree have differ- 

 ent vertical ranges. The nurseiy areas occupied 

 by the very young sharks are free of adults ex- 

 cept when the females come inshore to give birth 

 to their young. 



The migratory patterns of young and adults 

 differ greatly. Finally there is a well-defined 

 principal range occupied by at least nine-tenths 

 of the western Nortli Atlantic populaticm and an 

 accessory range of uncertain importance. It is 

 quite possible that the population occupying the 

 accessory range is not self-sustaining and exists 

 only because there is continuous but quite acci- 



