STIXG-KAYS. 



1097 



that only tho eyes iiiid spiracles are free. On being 

 alai'incid tiie-\- usually take to flight at once — and 

 bathers or waders theri'fore stir up the hottoni in front 

 of them with a stick, an oar, oi- the like, or 1)}' scrap- 

 ing their feet — but if accidental!)- trodden on, they 

 i)roniptly dart their caudal spine into the foot or leg, 

 inflicting an extremely painful, perhaps even a nioi'tal 

 wound. Alxnit fifty species are known — not all, how- 

 ever, armed with caudal spine — and among tluMu are 

 several (7) inhabitants of the Mediterranean, which 

 have rendered the family notoiious sijice j)rehistoric 

 times. A Greek mvth relates how the sorceress Cihoe 

 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 

 Odysseu.s, and ho\v 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 arc uiidi\ided, n(n'er deej)ly forked or lobed, 

 and the skin is sometimes almost entirely smooth; but 

 the extension of the jiectoi'al tins 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 oi' three compensatory spines in front of 

 the former. < hie dorsal tin is occasionally present 

 within this family, but there are never two. 



Dlmekil" divided the family into four subfamilies, 

 distinguished by the absence of the caudal spine {Uro- 

 rjlimni), or by the presence of a caudal fin {UroJophi), 

 of a dorsal tin ( Trfigonopterce), or by the absence of 

 both these tins (Pastii/acrf). To the last-mentioned 

 subfamily, which contains the greatest numlier of spe- 

 cies, belongs the 



Genl.s TRYGON'. 



One or more dagger-spines furnished with retral harbs on the tail. Where rerticcd dermal folds appear on the 

 tail, these are low and do not extend out to the tip thereof. No raged vertical fns. The transverse cleft 

 of the mouth almost straight or at most hut slightlg curved. Jaw-teeth (fig. 313) fattened, triangular, and set 

 in a dense quincimcial arrangement; in the males sharpened. Disk of the body rhomboidal, of almost equal 



bread til and length. 



Thus deiined the genus includes about a score' 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 Rox- 

 delet', "for this is yellow, but because of the resem- 

 blance of the pectoral tins to expanded wings." Among 

 the Romans the genus was called I'astinaca, a name 

 that RoxDELET derives from the colour and terete form 

 • if the tail, which in these Rays is like a parsnip. 



° ffisl. Nat. Poiss. (su. a BuFF.), tome I, p. 579. 

 * Adanson, Cotirs d'Histoire natureUe, 1772, vol. II, p. 170. 

 adopted the name of Trygon from it in 1809 (Descr. de I' Egyjite). 

 ' CtUNTliEK diagnoses 23 species in his Catalogue. 

 ■' De Pise, p. 332. 



This work first appeared in print in 1825; but Geoffr. St. Hil. 



