STING-RAYS. 
1097 
that only the eyes and spiracles are free. On being 
alarmed they usually take to flight at once — and 
bathers or waders therefore stir up the bottom in front 
of them with a stick, an oar, or the like, or by scrap- 
ing their feet — but if accidentally trodden on, they 
promptly dart their caudal spine into the foot or leg, 
inflicting an extremely painful, perhaps even a mortal 
wound. About fifty species are known — not all, how- 
ever, armed with caudal spine — and among them are 
several (7) inhabitants of the Mediterranean, which 
have rendered the family notorious since prehistoric 
times. A Greek myth relates how the sorceress Circe 
tipped with the spine of a Sting-Ray — or perhaps of 
an Eagle-Ray — the spear she gave to her son Tele- 
gonus, when he was setting out to seek his father 
Odysseus, and how this spine became the latter’s bane. 
The family occupies an intermediate place between 
the preceding and the following families. Often the 
head is perceptibly elevated, the eyes assuming almost 
the same position as in the preceding family, the ven- 
tral tins are undivided, never deeply forked or lobed, 
and the skin is sometimes almost entirely smooth; but 
the extension of the pectoral fins along the sides of 
the head ranges this family beside the true Rays. Se- 
veral of the forms are also furnished with vertical 
dermal folds, sometimes with a true caudal tin, on the 
superior or inferior caudal margin, sometimes on both. 
Most of them have a caudal spine and sometimes as 
many as two or three compensatory spines in front of 
the former. One dorsal tin is occasionally present 
within this family, but there are never two. 
Dumeril" divided the family into four subfamilies, 
distinguished by the absence of the caudal spine ( Uro - 
gymni ), or by the presence of a caudal tin {TJrolophi), 
of a dorsal tin ( Trygonopterce), or by the absence of 
both these fins ( Pastinacce ). To the last-mentioned 
subfamily, which contains the greatest number of spe- 
cies, belongs the 
Genus TRYGON'. 
One or more dagger-spines furnished with retral barbs on the tail. Where vertical dermal folds appear on the 
tail , these are low and do not extend out to the tip thereof. No rayed vertical fins. The transverse cleft, 
of the mouth almost straight or at most but slightly curved. Jaw-teeth {fig. 312 ) flattened , triangular , and set 
in a dense quincuncial arrangement; in the males sharpened. Disk of the body rhomboidal , of almost equal 
breadth and length. 
Thus defined the genus includes about a score 0 of 
ascertained species from tropical and temperate regions 
all round the globe. The generic name is of classical 
Greek origin, and occurs in many passages of Aris- 
totle’s works in its present signification, though it 
was originally applied to a dove. The notorious and 
dreaded Ray thus became the namesake of the symbol 
of innocence, “not on account of its colour,” says Ron- 
DELET fi , “for this is yellow, but because of the resem- 
blance of the pectoral fins to expanded wings.” Among 
the Romans the genus was called Pastinaca, a name 
that Rondelet derives from the colour and terete form 
of the tail, which in these Rays is like a parsnip. 
“ Hist. Nat. Poiss. (su. a Buff.), tome I, p. 579. 
b Adanson, Conrs d'Histoire naturelle, 1772, vol. II, p. 170. This work first appeared in print in 1825; but Geoffr. St. Hil. 
adopted the name of Trygon from it in 1809 ( Descr . de I'Egypte). 
c Gunther diagnoses 23 species in his Catalogue. 
d De Pise., p. 332. 
Fig. 312. Jaws and teeth of a Sting-Ray ( Trygon pastinaca), 9- 
Natural size. After Moreau. Within the figure teeth on a magnified 
scale. I, ligaments. 
