Online Dictionary of Invertebrate Zoology: Complete Work - Best Text

Online Dictionary of Invertebrate Zoology 301excretion in excess of the usual amount, directly referableto drinking, eating or certain metabolites.diurnal a. [L. diurnus, of the day] Pertaining to animals activeonly during the daytime. see nocturnal, crepuscular.diurnal eyes (ARTHRO: Chelicerata) In spiders, eyes that aredark in color.diurnal rhythm Having a 24 hour periodic cycle. see circadian.divaricate a. [L. divaricatus, spread apart] 1. Forked or dividedinto branches; diverging. 2. (MOLL: Bivalvia) Pertainsto ornamentation consisting of widely divergent costulae orother shell ornamentation.divaricator n. [L. divaricatus, spread apart] 1. A muscle whichcauses parts to open. 2. (BRACHIO) A muscle from theventral valve to the cardinal process which opens the shell.3. (BRYO) One of a pair of muscles which open the mandiblefor an avicularium or an operculum.divergent a. [L. diversus, different] Becoming more separateddistally; extending in different directions from the sameorigin.divergent adaptation Adaptation to different kinds of environmentalinfluence that results in a change from a commonancestral form.diverse a. [L. diversus, different] Being distinct; differing insize or shape; dissimilar; separate.diverticulum n.; pl. -ula [L. devertere, to turn away] An outgrowthor pouch of some sort from the main axis of an organ.divided a. [L. dividere, to separate] Parted or disunited.divided eyes (ARTHRO: Insecta) 1. One in which the ommatidiain one area are different in size and often in pigmentation.2. In many Odonata, the dorsal facets are nearly twice thediameter of the ventral ones. 3. In certain Hemiptera, theventral facets are larger. 4. In some coleopteran waterbeetles, the eye is divided transversely. 5. In certainEphemeroptera, the lateral pair are apposition eyes and thedorsal pair are superposition eyes.