1096 



SCANDINAVIAN FISHES. 



head — with the semicircular" or still more obtuse and 

 depressed snout — presents an appearance which was 

 compared by Rondelet to that of a toad's head, by 

 Johnston to the print of a horse's hoof, the great fon- 

 tanelle representing the impression left by the frog of 

 the hoof. The eyes are set so high that their superior 

 margin is almost in a plane with the forehead. Their 

 longitudinal diameter in the young is about half the 

 length of the snout, in old specimens less. Just behind 

 the eyes lie the large spiracles, the length of which is 

 about twice that of the former. The nostrils are ap- 

 proximated rather closely to each other, the dermal flap 

 which covers their internal jjarts (the nasal valvule) 

 being medially attached only at its base by a narrow 

 frenum. This valvule is trapezoidal in form, broad, 

 and expands behind to the truncate edge that lies, with 

 a shallow median sinus and fringed with papilla?, close 

 to the anterior margin of the mouth and outside the 

 very thin true upper lip. The underlip too is thin at 

 tlie middle, l)ut tliickened at the corners of the mouth. 

 The breadth of the mouth is about ^ ., of the distance 

 between it and the tip of the snout. 



The body is somewhat depressed (flattened) behind 

 the head, but a little further back rises again to the 

 shoulder-girdle, where the depth is about equal to the 

 length of the fontanelle mark on the top of the head. 

 In the median line behind this point there is a low 

 ridge, which passes on the tail into a dermal edge in 

 front of the dorsal fin, which is rounded above or 

 obliquely truncate. Behind this tin lies the spear-like 

 caudal spine, with faintly convex front, carinated 

 back, and numerous (40 — 50) retral barbs on the 

 sides''. 



The large triangular pectoral fins have been coin- 

 pared to the wings of an eagle, and have given the ge- 

 nus its vulgar name. The ventral fins are quadrangular, 

 with straight or somewhat convex posterior margin. 



The general features of the highly varialJe colo- 

 ration have already been indicated. 



The Eagle-Rav, which is known from Australia (Syd- 

 ney) — ])i'obably from Japan too — and from the Cape 

 of Good Hope, has its principal European habitat in the 

 Mediterranean and the neighbouring parts of the Atlantic. 

 (_)n the north-west coast of Fi'ance it is fairh' common, 

 but even on the English coast it is rare. Further 

 north it is still i-arer. On the IGth of November, 1882, 

 however, a young male" of this species was taken among 

 small Heri'ings at Vettre Farm in Asker, 20 kilom. 

 south of Christiania. The Herring-seine was drawn on 

 a clay bottom, at a depth of 12 — 14 fathoms (Collett). 



The habits of the Eagle-Ray essentially resemble 

 those of the Devil-fishes as described above. It is a 

 less marked bottom-fish than the true Raj's. It appears 

 to fly rather than to swim, says Mokeau, whether it 

 is traversing raid-water or lashing the surface with one 

 of its pectoral fins. An Eagle-Ray was kept in an aqua- 

 rium at Arcachon, the same author states, and whenever 

 it ^vas taken out of the ^\•ater, it uttered a rather loud 

 bellowing noise. Its flesh is of little value and is not 

 much eaten. On the other hand, it is greatly dreaded by 

 the fishermen for the sting of its sjiine. The tail is usually 

 chopped oft" before handling the fish. According to Mo- 

 REAU the Eagle-Ray is viviparous. A fisherman from Ros- 

 coff told him that a female of this species had given 

 birth to seven living young just after she had been 

 hauled into the boat. 



lAM TRYGONIDiE. 



The whip-like tad icith or iritlioiit either fins or spine. Pectoral fins extended irithoiit a break forward along 

 the sides of the head and contigaous in front of the tip of the snout. 



This family has its true home in tlie seas and 

 rivers of the tropics, where many of its members are 



a scourge to bathers. They generally live in shallow 

 water, concealing their body in the sand or mud, so 



" In a male 60 cm. long the leiigtli of the Hatteued snoul in the median line before the fontanelle is lialf its breadth at the 

 same point. 



*• In the specimen described by CoLLETT, the tailless body of which measured 318 mm. in lengtli, tlie true candal spine was 82 nnn. 

 long, but in front of it lay a compensatory spine, still covered with skin and 11 mm. long. In a male 66 cm. long, tlie tail of which 

 measured 40 cm., the former spine was 63 mm. long, the compensatory spine [ib mm. 



' Length of the body 853 mm., including the tail (535 mm.). (Ircalcst breadth (between the tips of tlie pectoral fius) 540 mm. 

 Length of the copulatory organs (pterygopodia) 78 mm. 



