54 DANGEROUS MARINE ANIMALS 



on both sides of the North Atlantic and North Pacific Oceans. Some 

 of its close relatives are widely distributed throughout temperate 

 and tropical seas. Dogfish are somewhat sluggish in their move- 

 ments, and seem to prefer shallow, protected bays for 'their habitat. 



Venom Apparatus. Wounds are inflicted by the dorsal stings 

 which are located adjacent to the anterior margins of each of the 

 two dorsal fins. The venom gland appears as a glistening, whitish 

 substance situated in a shallow groove on the back of the upper 

 portion of each spine. When the spine enters the skin, the venom 

 gland is damaged and the venom enters the flesh of the victim. 



Fig. 26. Spiny Dogfish, Sqiialus acanthias Linnaeus. Note the single spine in 



front of each of the dorsal fins. 



Medical Aspects. Symptoms consist of immediate, intense, stab- 

 bing pain, which may continue for a period of hours. The pain 

 may be accompanied and followed by redness and severe swelling of 

 the affected part. Tenderness about the wound may continue for 

 several days. According to some authors, dogfish stings have been 

 known to be fatal. 



Treatment. Treat as any other fish sting. (See Page 91) . 



Prevention. Stings usually occur from the careless handling of 

 dogfish. Be careful of the dorsal stings when removing the dogfish 

 from a spear, hook, or net. They can give a sudden jerk and drive 

 the sting deep into the flesh of a reckless fisherman. 



STINGRAYS 



Stingrays constitute one of the largest and most important groups 



of venomous marine organisms. There are said to be about 1500 



stingray attacks reported in the United States each year. Stingrays 



are divided into seven families : 



Dasyatidae — stingrays or whiprays Myliobatidae — eagle rays or bat rays 

 Potamotrygonidac — river rays Rhinopteridae — cow-nosed rays 



Gymnuridae — butterfly rays Mobulidae — devil rays or mantas 



U rolophidae — round stingrays 



