Definition of mollusca
Thanks for using this online dictionary, we have been helping millions of people improve their use of the english language with its free online services. English definition of mollusca is as below...
Mollusca (n. pl.) One of the grand divisions of the animal kingdom, including the classes Cephalopoda, Gastropoda, PteropodaScaphopoda, and Lamellibranchiata, or Conchifera. These animals have an unsegmented bilateral body, with most of the organs and parts paired, but not repeated longitudinally. Most of them develop a mantle, which incloses either a branchial or a pulmonary cavity. They are generally more or less covered and protected by a calcareous shell, which may be univalve, bivalve, or m
Lern More About Mollusca
Incurrent ::
Incurrent (a.) Characterized by a current which flows inward; as, the incurrent orifice of lamellibranch Mollusca..
Cambrian ::
Cambrian (a.) Of or pertaining to the lowest subdivision of the rocks of the Silurian or Molluscan age; -- sometimes described as inferior to the Silurian. It is named from its development in Cambria or Wales. See the Diagram under Geology.
Hepato-pancreas ::
Hepato-pancreas (n.) A digestive gland in Crustacea, Mollusca, etc., usually called the liver, but different from the liver of vertebrates..
Acephala ::
Acephala (n. pl.) That division of the Mollusca which includes the bivalve shells, like the clams and oysters; -- so called because they have no evident head. Formerly the group included the Tunicata, Brachiopoda, and sometimes the Bryozoa. See Mollusca..
Opisthobranchiata ::
Opisthobranchiata (n. pl.) A division of gastropod Mollusca, in which the breathing organs are usually situated behind the heart. It includes the tectibranchs and nudibranchs..
Conchology ::
Conchology (n.) The science of Mollusca, and of the shells which they form; malacology..
Bojanus Organ ::
Bojanus organ () A glandular organ of bivalve mollusca, serving in part as a kidney..
Cirrobranchiata ::
Cirrobranchiata (n. pl.) A division of Mollusca having slender, cirriform appendages near the mouth; the Scaphopoda..
Gastropoda ::
Gastropoda (n. pl.) One of the classes of Mollusca, of great extent. It includes most of the marine spiral shells, and the land and fresh-water snails. They generally creep by means of a flat, muscular disk, or foot, on the ventral side of the body. The head usually bears one or two pairs of tentacles. See Mollusca..
Streptothrix ::
Streptoneura (n. pl.) An extensive division of gastropod Mollusca in which the loop or visceral nerves is twisted, and the sexes separate. It is nearly to equivalent to Prosobranchiata..
Stomatoplastic ::
Stomatogastric (a.) Of or pertaining to the mouth and the stomach; as, the stomatogastric ganglion of certain Mollusca..
Placophora ::
Placophora (n. pl.) A division of gastropod Mollusca, including the chitons. The back is covered by eight shelly plates. Called also Polyplacophora. See Illust. under Chiton, and Isopleura..
Cirrus ::
Cirrus (n.) The external male organ of trematodes and some other worms, and of certain Mollusca..
Solenogastra ::
Solenogastra (n. pl.) An order of lowly organized Mollusca belonging to the Isopleura. A narrow groove takes the place of the foot of other gastropods.
Bivalve ::
Bivalve (n.) A mollusk having a shell consisting of two lateral plates or valves joined together by an elastic ligament at the hinge, which is usually strengthened by prominences called teeth. The shell is closed by the contraction of two transverse muscles attached to the inner surface, as in the clam, -- or by one, as in the oyster. See Mollusca..
Ceratobranchia ::
Ceratobranchia (n. pl.) A group of nudibranchiate Mollusca having on the back papilliform or branched organs serving as gills.
Conchifera ::
Conchifera (n. pl.) That class of Mollusca which includes the bivalve shells; the Lamellibranchiata. See Mollusca.
Random Fonts
Most Popular
