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Related to lapillus: Accretionary lapilli


Pyroclasts that range from 0.04 to 2.6 inches (1 to 64 millimeters) in diameter.



small rounded or irregularly shaped pieces of lava between the size of a pea and a walnut, ejected together with volcanic bombs and ash during volcanic eruptions. They are chunks of lava that have solidified in flight or fragments of volcanic and wall rock through which the eruption passed and which solidified earlier.

References in periodicals archive ?
34-mm threshold for drill hole diameter for smaller Nucella lapillus than 5 mm and above 5 mm preying on Mytilus trossulus and Mytilus edulis.
pugilis (Colton, 1905; Galindo-Perez, 2009) and other snails like Buccinun undatum (Hallers-Tjabbers, 1979), Nucella lapillus (Son & Hughes, 2000), Pomacea canaliculata (Avaca et al.
Reproductive failure in populations of the dog-whelk, Nucella lapillus, caused by imposex induced by tributyltin from antifouling paints.
Several studies on the morphology and morphometry of the sagitta, lapillus and asteriscus otoliths have already been made (VOLPEDO; ECHEVERRIA, 2000; BAREMORE; BETHEA 2006; CAMPANA, 2004; FURLANI et al.
These canals form chambers containing otoliths, the lapillus is included in the utriculus (figure 1), the sagitta in the sacculus and the asteriscus is included in the lagena (figure 2).
The most striking finding, which has not been reported previously in Nucella lapillus, the Atlantic dogwhelk, is that shell length increased at all 19 sites where samples were taken.
Hughes and Dunkin (1984) describe a similar behavior in the gastropod Nucella lapillus, which consumes the digestive gland and discards the mantle and foot when preying on mytilids.
yellow-brown, loam (one lapillus observed); friable; moderately developed 10-20 mm blocky breaking to 2-5 mm nutty and crumb structure; 0.