. Animate creation : popular edition of "Our living world" : a natural history. Zoology; Zoology. 29G THE LANCELET. apparently as an organ of prehension, and the tongue is supplied with a double row of smaller but powerful teeth on each side, acting on the jirinciple of a ras]5. The Myxine can scarcely be said to jjossess any bones, the only indi(-ation of a skeleton being the vertebral column, which is nothing more than a cartilaginous tube, through which a jirobe can be passed in either direction. The structure of the breathing-organs is very remarkable. A double row of branchial c
. Animate creation : popular edition of "Our living world" : a natural history. Zoology; Zoology. 29G THE LANCELET. apparently as an organ of prehension, and the tongue is supplied with a double row of smaller but powerful teeth on each side, acting on the jirinciple of a ras]5. The Myxine can scarcely be said to jjossess any bones, the only indi(-ation of a skeleton being the vertebral column, which is nothing more than a cartilaginous tube, through which a jirobe can be passed in either direction. The structure of the breathing-organs is very remarkable. A double row of branchial cells take the place of gills or lungs, and are supplied with water through a spiracle in the upper part of the head, and two little apertures on the under surface. The color of the Hag-fish is dark brown above, taking a paler tint on the sides, and grayish-yellow below. Its length is generally about a foot or fifteen inches. The last of the fishes is a creature so unfish-like that its real position in the scale of nature was long undecided, and the strange little being has been bandied about between the vertebrate and iuvert«l)rate classes. Between these two great armies the Lancelet evidently occupies the neutral ground, its structure partaking with such apparent equality of the characteristics of each class, that it coidd not be finally refeired to its proper rank until it had been sub- mitted to the most cai'eful dissections. In fact, it holds just such a jjosition between the vertebrates and invertebrates as does the lepidosiren between the rei)tiles and the fishes. It has no definite brain, at all events it is scarcely better defined than in many of the insect tribe, and is only marked by a rather increased and blunted end of the spinal cord. It has no true heart, the place of that organ being taken by i)ulsating vessels, and the blood being. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - colora
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Keywords: ., bookauthorbr, bookcentury1800, bookdecade1890, booksubjectzoology
