定義: A landform consisting of loose rock particles such as sand, gravel, shingle, pebbles, cobble, or even shell fragments along the shoreline of a body of water.
定義: A group of hydrous aluminium phyllosilicate (phyllosilicates being a subgroup of silicate minerals) minerals (see clay minerals), that are typically less than 2micrometres in diameter. Clay consists of a variety of phyllosilicate minerals rich in silicon and aluminium oxides and hydroxides which include variable amounts of structural water.
定義: Planktotrophic species generally have fairly long pelagic larval durations and feed while in the water column. Consequentially, they have the potential to disperse long distances.
定義: Museum für Naturkunde Berlin (Zoological Collections) (ZMB). Berlin, Germany. URL for main institutional website: http://www.naturkundemuseum-berlin.de Formerly Zoologisches Museum der Humboldt-Universität zu Berlin
定義: Eye-spots which may be set into a pit to reduce the angles of light that enters, to allow the organism to deduce the angle of incoming light. Lens-like structures may be present, but stemmata, unlike lens eyes, cannot form an image, either for lack of refractive power or retinal resolution.