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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated.1903 Excerpt: ... following characters as common'to both groups: (i) the parapophyses are developed on all the abdominal vertebrae; (2) the supraclavicle when present is small; (3) the exoccipitals are not united above the basioccipital; (4) the supraclavicle, when present is reduced in size; (5) Fistularia and Aulostomus have processes running backward from the epiotics, which are strikingly similar to the epiotic processes possessed by all the Percesoces. On the other hand, the Hemibranchs easily stand apart from the Percesoces "in having no opisthotics and usually no parietals; in having the posttemporals simple, not typically forked; and in having the clavicle composed of a single piece when present (composed of two pieces in the Percesoces)." The most generalized form, Gasterosteus, is carnivorous and active, but the prey is the small "fry" of other fishes which the Sticklebacks seek out "with the utmost industry, sagacity, and greediness." The taste for minute prey to be sought by poking about in odd corners may have determined some of the peculiar specializations of the Sea-horse order. We may imagine these to have continually sought smaller and smaller food until the tiny particles came to be sucked up by the elongate muzzle. After probably passing through a stage somewhat like Syngnathus but less eel-like the ancestral Sea-horse did not need the quickdarting form of body to capture its food or escape enemies; hence the fan-like tail fin was suppressed (in Hippocampus), and the rapidly vibrating pectoral and dorsal fins enabled the fish to poise, humming-bird fashion, while sucking food through its tubular beak. The pectoral fins have been thought also to assist in drawing a steady current of water through the gill chamber. At a a very early period protection was sec...
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