. The Cambridge natural history. Zoology. OSTARIOPHYSI 595 Callichthys. There are other sexual differences in many species of Plecostomus, Chaetostomus, and Loricaria, as the presence of dermal tentacles on the snout (see Pig. 359), or of hair-like bristles on various parts of the head and fins in the males, which are usually of larger size. About 200 species are known, all from the tropical and sub- tropical parts of Central and South America. The largest species (Chaetostomus gigas) measures 1\ feet; many are of very small size.^ The genera may be referred to two sub-families :— (i.) Akginae
. The Cambridge natural history. Zoology. OSTARIOPHYSI 595 Callichthys. There are other sexual differences in many species of Plecostomus, Chaetostomus, and Loricaria, as the presence of dermal tentacles on the snout (see Pig. 359), or of hair-like bristles on various parts of the head and fins in the males, which are usually of larger size. About 200 species are known, all from the tropical and sub- tropical parts of Central and South America. The largest species (Chaetostomus gigas) measures 1\ feet; many are of very small size.^ The genera may be referred to two sub-families :— (i.) Akginae.—Body naked; ribs strong. Arges, Stygogenes, Astroilepus. (ii.) LORICARIINAE.—Body cuirassed by bony plates ; ribs very slender. Plecostomus, Liioosarcus, Chaetostormis, Cochliodon, Pterygoplichthys, Rhinelepis, Acanthicus, Otocinclus, Hypopto- poma, Loricaria, Fig. 360.—Acestra gladius, from the Jurua River, with upper and lower views of head and truiilt. (§ nat. size.) The " Prenadillas " of the Andes, Arges and Stygogenes, were believed to live in subterranean waters within the bowels of active volcanoes, and to be ejected with streams of mud and water during eruptions, a story that has been repeated by Humboldt. The fact is that they live in small torrents at great altitudes (up to 10,700 feet), and are swept down during periods of disturbance caused by the eruption of the volcano.^ The members of the sub- family Loricariiuae vary much in the shape of the body, which may be short and stout, or more or less slender, the extreme in the latter respect being attained by the species of the genus Acestra. ^ A monogi'aph of these Fishes, by Mr. C. T. Regan, will shortly appear in the Transactions of the Zoological Society. 2 Cf. Jloritz Wagner, Abh. Alcad. Milnch. x. 1866, p. 101, and Whymper, Trav. Andes Ecuador, 1892, p. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability -
Size: 2860px × 874px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1895
