. Elements of comparative zoology. Zoology. manhaitensis^ BRANCH II.—LEPTOCARDII (LANCELETS). The few species of lancelets (Amphioxus} are all marine and occur in warmer seas. They have a body which is fish-like, but thev differ from all fishes in the absence of a «/ true heart and of a skull. The gill-slits are numerous. FIG. 100.—Diagram of Amphioxus (after Hertwig and Boveri). Above (dotted) is the nervous system; below it (cross-lined), the notochord; the mouth is surrounded by the circle of tentacles; below the notochord is the region of gill-slits; the vent is near the posterior (right)
. Elements of comparative zoology. Zoology. manhaitensis^ BRANCH II.—LEPTOCARDII (LANCELETS). The few species of lancelets (Amphioxus} are all marine and occur in warmer seas. They have a body which is fish-like, but thev differ from all fishes in the absence of a «/ true heart and of a skull. The gill-slits are numerous. FIG. 100.—Diagram of Amphioxus (after Hertwig and Boveri). Above (dotted) is the nervous system; below it (cross-lined), the notochord; the mouth is surrounded by the circle of tentacles; below the notochord is the region of gill-slits; the vent is near the posterior (right) end below. (about sixty), and these empty into a gill-chamber recall- ing in some features that of the tadpoles. The notochord runs the whole length of the body, and a stomach is lack- ing, the liver emptying into the intestine just behind the gills. Limbs or paired fins are absent, but there is a median fin at the end of the body. The animals are about two or three inches long, are almost perfectly transparent, and bury themselves in the sand, only the mouth end,. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Kingsley, J. S. (John Sterling), 1854-1929. New York, H. Holt and Company
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectzoology, bookyear1904
