. Elements of zoology, to accompany the field and laboratory study of animals. Zoology. 180 (Fig. 169). Some of the fresh-water forms make loose, antler- hke colonies (Fig. 170), while others lie on the surface of a more or less spherical mass of jelly which they have themselves secreted. The lamp-shells (Brachiopoda) are a vanishing class. Their fossil remains crowd the rocks almost from the first appearance of organic remains. While thousands of fossil species have been described, only about 125 li\'ing species are known, — all marine. Although the individuals are usually numerous i
. Elements of zoology, to accompany the field and laboratory study of animals. Zoology. 180 (Fig. 169). Some of the fresh-water forms make loose, antler- hke colonies (Fig. 170), while others lie on the surface of a more or less spherical mass of jelly which they have themselves secreted. The lamp-shells (Brachiopoda) are a vanishing class. Their fossil remains crowd the rocks almost from the first appearance of organic remains. While thousands of fossil species have been described, only about 125 li\'ing species are known, — all marine. Although the individuals are usually numerous in localities where they occur, the localities are few. In our country they are found on the coast of Alaine and Fig. 172.— The brarhiopod Magr-iiania, near Cape Hatteras. The with the ventral valve removed, c;), the .p, ,. i v "cardinal" projection of shell; \p)u the 1-SrachlopOda have a tWO- bearer of the tentacles " lophophoie" ; yglyed shell like a clam, Iph, its coiled ami, the tentacles removed from right side ; mlh, mouth. From Par- but the valves are not ker and Haswell. ^j^j^^ ^^^_^ jp^^_ ,^^^ ^j^^^^j and ventral (Fig. 171), and consequently have nothing to do with the shells of mollusks. The body somewltat resembles that of a single iitdividual of a Bryozoan colony — two arms stand \x\) on the right and l(>ft of the mouth and these are crowded with tentacles whose cilia create a vortex in the water, bringing small particles to the mouth (Fig. 172). The food canal is bent like a U, the loop of the U being at the hinge of the valves, half buried in the sand, while mouth and arms are elevated into the surrounding water. On account of the fact. 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 Davenport, Charles Benedict, 1866-1944; Davenport, Gertrude Anna Crotty, 1866- joint
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectzoology, bookyear1911
