14G ACANTHOPTEETGII. 



1. Xipliias gladius, Plate XLIX, fig. 1 and 2. 



!Si(piaQ, Arist. ii, c. 13, 15, viii, c. 19; Athen. vii, p. 314; ^lian, ix, c. 40, 

 xiv, c. 23 ; Oppian, i, 8, ii, 48. 



X-ipMas, Ovid. Hal. v, 67 ; Pliny, lib- xxxii, c. 2 ; Rondel, viii, c. 15, p. 251, 

 c. fig. ; Gesner, p. 1049 and 1598, f. 20, c. fig. ; Artedi, Syn. p. 30. L'Eeron 

 de mer, Bellon. Xipliia sm gladio, Jonston, De Pise. lib. i, tit. 1, c. i, Art. 3, 

 t. iv, f. 2. Swordlif:],, Willn-liby, Ich. p. 161, t. 1, 27, f. 2 ; Ray, p. 62 ; Pennant, 

 Brit. Zool. (Ed. i) iii, p. IGo, pi, xxvi (Ed. 2), iii, p. 216, pi. xxx. Spada, Cetti, 

 Hist. Sard, iii, pp. 93, 94, 146. Poisson a Upee, Duhamel, ix, p. 334. 



Xipliias gladiiix, Linn. Syst. i, p. 432 ; Blocb, t. Ixxvi ; Gmel. Linn. p. 1149; 

 Bonnaterre, Ency. Ich. p. 42, pi. xxvi, p. 92 ; Laoep. ii, p. 290, pi. ix, f. 1 ; Bl. Sclin. 

 p. 93 ; Shaw, Zool. iv, p. 99, pi. xiv ; Elem. Brewster's Jonrnal, ii, p. 187, and 

 Brit. An. p. 220 ; Turton, Brit. Fauna, p. 88 ; Risso, Icli. Nice, p. 99 and Eur. 

 Merid. iii, p. 208 ; Cuv. and Val. viii, p. 255, pi. ccxxv, ccxxvi; Storer, Report, 

 p. 51 ; Tan-ell, Brit. Eisli. (Ed. 1) i, p. 143, o. fig. (Ed. 2), i, p. 164 (Ed. 3), ii, 

 p. 240 ; Jenyn's Manual, p. 364 ; Parnell, Pislies Firth of Forth, p. 55, and 

 Wern. Mem. vii, p. 215 ; Cuv. Regno Anim. Illus. Poiss. pi. 1, f. 1, and 

 pi. Ii, f . 2, and pi. liii, f. 2 ; Demid. Voy. Russ. Merid. iii, p. 393 ; Swainson, 

 Fishes, ii, p. 239 ; Thompson, An. and Mag. (2), 1846, p. 314, and Nat. Hist. 

 Ireland, iv, p. 95 ; Gnichen. Expl. Sc. Alger. Poiss. p. 60 ; White, Catal. Brit. 

 Fish. p. 33 ; De Kay, New York Fauna, p. Ill ; Lowe, Trans. Zool. Soc. iii, p. 5 ; 

 Nilss. Skan. Fauna, p. 147 ; Giinther, Catal. ii, p. 511 ; Steind. Sitz. Ak. Wiss. 

 Wien, Ivii, p. 396, or Ich. Span. u. Port. 1868, p. 46 ; Schlegel, DierenNeder. p. 10, 

 pi. i, f. 3, 4; Hector, Ti-ans. New Zealand Inst, vii, p. 246 ; Collett, Norges Fiske, 

 p. 51 ; Winther, Ich. Dan. Mar. 1879, p. 16 ; Giglioli, Catal. Peso. Ital. 1880, 

 p. 28 ; Liitken, Spol. Atlan. p. 502 ; Moreau, Poiss. France, ii, p. 526. 



Xiphias liondeletii, Leach, Wern. Mem. ii, p. 58, pi. ii, f. 1, and Zool. Misc. 

 i, p. 62, pi. xxvii. 



Sii'OrdJish, Couch, Fish. Brit. Isles, ii, p. 145, pi. xcvii. 



B. vii, D. 3/43, P. 15, A. 17, C. 21. 



In the example figured, which is 30 inches long, the extreme length of the 

 head equals the distance between the head and base of the caudal fin. Eye — 

 3j diameters in the postorbital portion of the head. Interorbital space nearly 

 flat. Angle of preopercle crennlated. Snout depressed and flattened : the cleft 

 of the mouth reaching to nearly 1/2 a diameter posterior to the orbit. The 

 difllerent proportions vary with age, and in the vei'y young there are some 

 denticulations above the orbit, and t^'O short spines at the angle of the preopercle. 

 Teeth — true ones absent. Fins — vary exceedingly -with age : in the very young 

 (see page 148) the dorsal fin commences on the occiput and is continued until 

 near the tail, but it is slightly elevated anteriorly ; in the rest of its course it is 

 several times higher than the body. As the fish increases in age, as about 

 2^ or 3 feet in length (plate xlix), the middle portion of the dorsal fin commences 

 to decrease in height, showing the anterior rays much elevated and also the last 

 few. The middle portion becomes more and more absorbed, until in the adult 

 there are two distinct dorsal fins. The anal undergoes a transformation similar 

 to the dorsal. Pectoral placed very low down and falciform. Scales —rudimentary. 

 Been in the very young in the form of t^vo rows along the side of the dorsal 

 fin, and also along the abdominal edge. Alr-ihiMer — large, and with thin 

 walls. Cntiinrs — back and upper half of the body of a dull blue or brownish 

 blue, becoming white on the sides and beneath. The young have transverse 

 bands. 



Varieties. — It is possible that the following are merely varieties of this species, 

 but sufficient materials hardly exist in museums at present to decide the question. 

 Xipliias nigricans, Lacepede, and Histiophorus gracilirostris, Cuv. : also Xipliias 

 vrlifer, Cuvier. The lateral keel on the side of the tail may be double, and the 

 dorsal fin lower or higher than the trunk. 



