74 GIANT FISHES 



autumn. The largest British specimen was 3^ feet in length 

 and weighed 56 lb. 



With these rays we encounter a further stage in specializa- 

 tion, the tail having become a mere appendage, useless alike 

 for locomotion or for steering. 



The principal feature of these fishes, and one from which 

 they derive their name, is the presence of a sharp spine with 

 jagged saw-like edges on the back of the tail. This " sting " 

 may be anything from 3 to 12 or even 15 inches in length, 

 and when worn out is replaced by a new one growing up 

 behind it. Sometimes 2 or even 3 may be present at the 

 same time. There can be little doubt that these " stings " 

 are of essentially the same nature as the dermal denticles, 

 and must have arisen in the first place either through the 

 enlargement and specialization of a single denticle, or through 

 the fusion of several denticles lying close together in the 

 middle line of the back of the tail. 



This spine provides a truly formidable weapon, and, when 

 the tail is lashed furiously from side to side, is capable of 

 inflicting a very nasty wound. Normally it would appear 

 to be used as a defensive weapon, but Sting Rays have been 

 observed to encircle prey with their whip-like tails and to cut 

 and pierce them with the spines. Dr. Jordan has described 

 how he saw one Sting Ray thrust the spine through the body 

 of another lying near it in a boat. Dr. Coles mentions an 

 individual weighing 64 lb., caught off the coast of Carolina, 

 which, when prodded with a lance, " exhibited great fury 

 and time and again threw itself on its back as it slashed at 

 me with its barbed tail. It would give forth a loud, harsh, 

 discordant bark of baffled rage at its failure to reach 

 me . . . " 



The ancient writers had fearful tales to tell concerning the 

 wounds caused by the Trygon, and we read that " Circe armed 

 her son with a spear which she pointed with a Trygon' s spine 

 as the most formidable weapon she could place in his hands, 

 and with which he subsequently unintentionally slew his 

 father, Ulysses ". " Nothing is more terrible," writes 

 Pliny, " than the sting that arms the tail of Trygon, called 

 Pastinaca by the Latins, which is five inches long. When 

 driven into the root of a tree it causes it to wither. It can 



