270 UNDERWATER GUIDE TO MARINE LIFE 



The common trunkfish, Lactophrys trigonias (/ig. 150^, is like the shellfish 

 in distribution and coloration, but is smaller and has black bases to the fins. 



A species with a spine over each eye, Ostracion diafhanutn, is reported by 

 Barnhart (1930) to have been picked up dead on southern California beaches. 

 It should be looked for. 



PUFFERS: Family Tetraodontidae 



These fishes possess the almost unique ability, along with the swell shark, of 

 inflating themselves with either air or water or both so that they assume an 

 almost globular shape. They are able to do this very quickly, and by this means 

 they make themselves larger to discourage enemies which would otherwise attack 

 them. When swollen with air, they bob helplessly, belly up at the surface. Defla- 

 tion is accompanied by ludicrous belching noises and bubbling at the mouth. 



Puffers can make a grinding noise by rubbing their teeth together. The teeth 

 of puffers are fused into a beak which is divided by a median suture, hence the 

 name "Tetraodontidae," meaning "four-toothed." They eat shellfish such as 

 crab and molluscs as well as other invertebrates, cracking them with this beak. 

 They swim by using the pectoral, dorsal, and anal fins principally. Puffers are 

 mostly small, active little fishes which nose about reef and sandy bottom areas 

 in tropical seas. 



Many species develop poisons in their liver and gonads, or more rarelv in the 

 flesh. It is not known what causes some puffers to become poisonous and 

 some not. The eggs are known to carry poison, and if a puffer ate its own eggs, 

 as some are known to do occasionally, this might cause the liver or even the 

 flesh to become poisonous also. However, the nature of fish poisoning is very 

 poorly known (Chapter 4). 



RABBiTFiSH (sMOOTH puffer) : Lagocephaliis laevigatus— Color Plate 9 



Size: Up to 2 feet. Largest of the puffers. 



Weight: Up to 7 pounds. 



Distrihution: West Indies to Cape Hatteras. Straggles to Cape Cod. 



Identification: The color is silvery, becoming greenish above. The head is 

 blunt compared to other puffers. There is a fold of skin on the lower body 

 especially posteriorly. 



Habits: Rabbitfish are not able to distend their bodies as greatly by swelling 

 as other puffers, a fact no doubt related to their alreadv large size. They swim 

 over a wide variety of sandy or hard bottoms and are found in harbors, but they 

 prefer shallow channel waters. Their food consists of crustaceans and molluscs. 



SOUTHERN puffer: Sfheroidcs spengleri— Color Plate 9 



Size: Lip to 1 foot or more. Mostly seen under 8 inches. 



Distrihution: West Indies to Florida. Strapgles to Massachusetts. 



Identification: There are a series of black spots along the sides. The tail fin 

 has two black bands, one at the base and one at the tip. 



Hahits: This species can distend itself to an extreme degree. Normally it is 

 quite slim. Even the young are able to swell up, forming curious little pea-sized 

 balloons. This is a common fish in shallow waters in harbors and over sandy 

 bottoms. It has been seen attacking large crabs in groups, one fish biting the crab, 

 then another, until the crab is immobilized. Even so small a puff"er has a beak 



