44 DANGEROUS MARINE ANIMALS 



cases, paralysis may be present. Respiratory distress is usually 

 absent. Coma may ensue, and death is said to be the result of 

 cardiac failure. 



Treatment. There is no specific treatment. Cases of cone shell 

 stings should be managed like venomous fish stings. See page 91. 



Prevention. Live cone shells should be handled with care, and 

 effort should be made to avoid coming in contact with the soft parts 

 of the animal. 



Cephalopods 



This group includes the nautilus, squid, cuttlefish, and octopus. 

 The head is large and contains conspicuous and well-developed eyes. 

 The mouth, armed with horny jaws and a radula, is surrounded by 

 eight or ten tentacles equipped with numerous suckers or hooks. 

 Rapid movements can be produced by expelling water from the 

 mantle cavity through the siphon. 



Few marine animals have received greater attention from fiction 

 writers than has the octopus. Truly, it is a remarkable creature, 

 but it is grossly overrated as a hazard to the diver. The octopus is 

 a curious animal, but cautious, and can hardly be considered the 

 demon of the seas that many writers make it out to be. Large speci- 

 mens may exceed 25 ft. in span, but those encountered at diving 

 depths are generally smaller. The giant squid that is commonly 

 taken off the coast of South America may attain several times the 

 length of the largest octopus, but are for the most part deep water 

 inhabitants, and of little interest to skin divers. The nautilus and 

 cuttlefish are not considered to be of medical importance. Octopuses 

 tend to hide in holes, or underwater caves. Areas such as this should 

 be avoided by the inexperienced diver. There is a danger, remote 

 that it may be, of a diver being trapped underwater when entering 

 such a cave, even by a relatively small specimen, if it can get a good 

 grip on a smooth surface of the diver. A more practical danger 

 comes from the careless handling of even small specimens of octo- 

 puses, since these animals possess a well-developed venom apparatus 

 and produce their injurious effects by biting. 



Species of Cephalopods. Since cephalopods can be identified only 

 with difficulty by specialists, no attempt will be made to consider 

 individual species. The colored Frontis shows the common octopus, 

 Octopus vulgaris Lamarck, and the squid, Loligo vulgaris Lamarck, 

 which are found in many parts of the world. 



Venom Apparatus of the Octopus. The venom apparatus of the 

 octopus is comprised of the so-called anterior and posterior sali- 



