[7] MATERIALS FOR A HISTORY OF THE SWORD-FISHES. 295 
lated. Air-bladder present, simple (Xiphiinc) or cellulated ( Tetrapturus 
and Histiophorus(?). Intestine long, sinuous (Xiphiine), or short, not 
sinuous (Tetrapturinw). Gall-bladder free, hanging at some distance 
from the liver. <Articular processes developed from the parapophyses. 
Synopsis of subfamilies. 
Ventrals absent, skin scaleless, snout flat, caudal keel single... XIPHIINZ, Swainson. 
Ventrals present, skin with scutes, snout rounded, caudal keels double. 
HISTIOPHORINZ, Liitken. 
6.—DESCRIPTION OF THE SUBFAMILY XIPHIINA: AND THE GENUS 
XIPHIAS. 
Subfamily X1PHIINz, Gill. 
> Xiphyine, SWAINnsoNn, Nat. Hist. Fish. Amphib. etc. 1839, p. 239. 
> Xipheini, BONAPARTE, Cat. Metod. Pesci Europei, 1846, p. 80. 
Xiphiine, GILL, Canadian Naturalist, 1867, p. 250. 
Diagnosis of subfamily. 
Xiphiid fishes, with bodies somewhat compressed, scaleless, or in 
young sate covered with rough granulations. Sword flattened hori- 
zontally. Teeth absent. Pectorals sublateral. Pelvic arch and ven- 
trals absent. A keel upon each side of the caudal peduncle. Air-blad- 
der simple. Intestine long, sinuous. A single genus, XIPHIAS, L. 
Genus Xiphias, Artedi. 
Xiphias, ARTEDI, Genera Piscium, 1738, p. 29. 
Xiphias, LINNZUS, Syst. Nat. ed. x, 1758, p. 248; ed. xii, p. 432. 
Xiphias, CUYIER, Regne Animal, 1817, p. 326, 1829, p. 200. 
Aiphias, GUNTHER, Cat, Fish. Brit. Mus ii, p. 511. 
Diagnosis of genus. 
Xiphiine fishes, with two dorsal fins in adult condition, the continu- 
ous dorsal of the young having become rudimentary in its median por- 
tion. Preeperculum spineless in adult, the large spine of the young 
disappearing at an early age. ‘Teeth absent “ except upon the pharyn- 
geal bones, which are covered with a villosity of extremely fine and 
minute denticles” (Owen). Number of dorsal rays probably variable. 
Vertebree 26 (Steindachner). Branchiostegals 7. Stomach siphonal, 
pyloric ceca very numerous. Gall-bladder large. 
HApirat.—Tropical and temperate parts of the Atlantic, Mediter- 
ranean, New Zealand, and South Pacific north to California. 
A single species of this geuus is now known, Xiphias gladius, L. The 
species recorded in GUNTHER’S Catalogue of the Fishes in the British 
Museum, vol. ii, p. 512, under the name Xiphias velifer, if not mythical, 
is probably a Histiophorus. Lacépéde’s figure represents it with two 
caudal carinz, and, what is stranger, without ventrals. 
