290 MANUAL OF ZOOLOGY. 



AMCEBIFORM. Eesembling an Amceba in form. 



AMORPHOZOA (Gr. a, without ; morphe, shape ; soon, animal). A name 



sometimes used to designate the Sponges. 

 AMPHIDISCS (Gr. amphi, at both ends ; disJcos, a quoit, or round plate). 



The spicula which surround the gemmules of Spongilla, and resemble 



two toothed wheels united by an axle. 



AMPHIPODA (Gr. amphi, and pous, a foot). An order of Crustacea. 

 ANALOGOUS. Applied to parts which perform the same function. 

 ANARTHROPODA (Gr. a, without ; arthros, a joint ; and pous, foot). That 



division of Anmdose animals in which there are no articulated appen- 

 dages. 

 ANDROGYNOUS (Gr. aner, a man ; gune, a woman). Synonymous with 



hermaphrodite, and implying that the two sexes are united in the same 



individual. 

 ANDROPHORES (Gr. aner, a man ; and phero, I carry). Applied to medusi- 



form gonophores of the Hydrozoa, which carry the spermatozoa, and differ 



in form from those in which the ova are developed. 

 ANNELIDA (a Gallicised form of Annulata). The Einged Worms, which form 



one of the divisions of the Anarthropoda. 

 ANNULATED. Composed of a succession of rings. 

 ANNULOIDA (Lat. annulus, a ring; Gr. eidos, form). The sub-kingdom 



comprising the Echinodermata and the Scolecida ( = Echinozoa). 

 ANNULOSA (Lat. annulus]. The sub-kingdom comprising the Anarthropoda 



and the Arthropoda or Articulata, in all of which the body is more or 



less evidently composed of a succession of rings. 



ANOMURA (Gr. anomos, irregular ; oura, tail). A tribe of Decapod Crus- 

 tacea, of which the Hermit Crab is the type. 

 ANOPLURA (Gr. anoplos, unarmed; oura, tail). An order of Apterous 



Insects. 



ANTENN.E (Lat. antenna, a yard-arm). The jointed horns or feelers, pos- 

 sessed by the majority of the Articulata. 

 ANTENNULES (diminutive of antennce}. Applied to the smaller pair of 



antennae in the Crustacea. 

 ANTLIA (Lat. antlia. a pump). The spiral trunk or proboscis with which 



Butterflies and other Lepidopterous insects suck up the juices of flowers. 

 APHANIPTERA (Gr. aphanos, inconspicuous ; and pteron, a wing). An order 



of Insects, comprising the Fleas. 

 APODAL (Gr. a, without; pous, foot). Devoid of feet. 

 APODEMATA (Gr. apodaio, I portion off). Applied to certain chitinous 



septa which divide the tissues in Crustacea. 

 APTERA (Gr. a, without; pteron, wing). A division of Insects, which is 



characterised by the absence of wings in the adult condition. 

 APTEROUS. Devoid of wings. 

 ARACHNIDA (Gr. arachne, a spider). A class of the Articulata, comprising 



Spiders, Scorpions, and allied animals. 

 ARBORESCENT. Branched like a tree. 

 ARENACEOUS. Sandy, or composed of grains of sand. 

 ARTICULATA (Lat. articulus, a joint). A division of the animal kingdom, 



comprising Insects, Centipedes, Spiders, and Crustaceans, characterised 



by the possession of jointed bodies or jointed limbs. The term Arthro- 

 poda is now more usually employed. 

 ASCIDIOIDA (Gr. askos, a bottle ; eidos, form). A synonym of Tunicata, a 



class of Molluscous Animals, which have the shape, in many cases, of a 



two-necked bottle. 

 ASEXUAL. Applied to modes of reproduction in which the sexes are not 



concerned. 



