THE LOWER FISHES 



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Fig. 6?>. Lemon shark. 



Hahits: This is a strictly inshore shark and may be seen around harbors and 

 sounds. It even enters such fresh waters as the Amazon. It is mainly a fish-eater. 

 It is one of the most common of Caribbean sharks and is not to be trusted, its dis- 

 position supposedly being erratic. This shark is viviparous, bearing young in 

 the spring and summer. 



GROUND sharks: Carcharinus species 



This is the largest genus of sharks, containing many species that are difficult 

 to identify even by experts. Therefore, they will be considered as a group. 

 Their distribution is world-wide in warm temperate and tropical waters. 



Identification: As a group, the ground sharks are bluish or grayish to brownish, 

 generally lighter on the belly. The first dorsal is very high and placed forward. 

 The second dorsal is over the anal and, like the anal, is small. The upper pre- 

 caudal pit is very large. There is no spiracle. 



Hahits: These are inshore and reef-inhabiting sharks of fish-eating habits 

 largely, but they will take many foods. The larger ones are not to be trusted. 

 The teeth are trenchant and large. When the cry "shark" goes up along inshore 

 waters, the cause is usually a ground shark. They are curious fish and have 

 approached the authors to within a foot, returning several times for repeated 

 "looks," but seldom gave trouble. In fact, they usually fled when approached, 

 but that is no guarantee that they invariably do so. One, the Lake Nicaragua 

 shark, Carcharinus nicaragiiensis, is the only habitually fresh-water shark and 

 has been known to attack people. A list of the most common species with hints 

 for identification follows: 



East Coast: 



1. Cub Shark (Bull Shark, Fish Shark, Southern Ground Shark): 

 C. Leiicas 



This species is never found far from land. It frequently travels in groups. 

 The diet is extremely varied, this shark can be dangerous at times. The 

 snout is very short, broad, and rounded for the genus. It attains a length 

 of 10 to 12 feet, though rare over 8 feet. From Cape Hatteras to Brazil 

 and strays to Massachusetts. 



2. Small Black-Tipped Shark (Spinner Shark): C. linihatus 



The eyes are large, and the pectoral, dorsal, anal and lower caudal fins 

 are tipped with black. It is rather small, averaging 6 feet and reaching 

 9 feet. This is an active, swift, largely pelagic species. It may school at the 



