. A manual of zoology. MANUAL OF ZOOLOGY Fig. 103.—Pedicellina. Showing successive stages (numbered / to 6) in the development of zooids by budding, an, anus ; gang, ganglion ; mo, mouth ; tent, tentacles (retracted). (After Hatschek.) 3. THE BRACHIOPODA The Brachiopoda, or Lamp-shells, are a group of marine animals which present certain important features of resemblance to the Folyzoa, and on that account are placed with them in a special phylum to which the name Molluscoida is applied. The Brachiopoda are solitary, never giving rise to colonies like those of the Polyzoa, and one of th
. A manual of zoology. MANUAL OF ZOOLOGY Fig. 103.—Pedicellina. Showing successive stages (numbered / to 6) in the development of zooids by budding, an, anus ; gang, ganglion ; mo, mouth ; tent, tentacles (retracted). (After Hatschek.) 3. THE BRACHIOPODA The Brachiopoda, or Lamp-shells, are a group of marine animals which present certain important features of resemblance to the Folyzoa, and on that account are placed with them in a special phylum to which the name Molluscoida is applied. The Brachiopoda are solitary, never giving rise to colonies like those of the Polyzoa, and one of their most striking characteristics is the possession of a calcareous shell which bears a remarkable resemblance to that of the members of a widely different group, the Pelecypoda of the phylum Mollusca, the group to which the mussels, oysters, and clams belong. The shell (Fig. 104) consists of two pieces or valves, one dorsal (</. v), the other ventral (v. v), and the animal is attached by a horny stalk or peduncle (Fig. 105, pd) which passes through an aperture (Fig. 104/") in a process, the beak (<^), of the ventral valve. In the natural state the peduncle is attached to a rock or other support, and the animal lies with the ventral valve uppermost and the two valves gaping slightly. The end of the valve at which the peduncle is situated is regarded as posterior, the. 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 Parker, T. Jeffery (Thomas Jeffery), 1850-1897; Haswell, William A. (William Aitcheson), 1854-1925. New York, The Macmillan Company; London, Macmillan & Co. ,Ltd.
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