AM(EBA 



18 



AMPHITHEATRE 



tebrata, including all those of which the 

 frBtus has an amnion; also called Abranchi- 

 ate Vertebrata, q.v. 



Amoeba, (am-e'ba). [Gk. avzoibe, permuta- 

 tion.] Simple microscopic organisms, found 

 in the alimentary canal of cockroaches, &c. , 

 almost the simplest known forms of animal 

 life, take in food at any point of the body, 

 and undergo several changes of form, hence 

 also called Proteus. Belong to Rhizopoda. 



Amomal.es, (am-6-ma'lez). [Amomum, q.v.] 

 Plants found in hot climates, resembling the 

 Amomum, having petaloid flowers and leaves 

 with diverging veins. Ex., Banana, Gin- 

 ger-plant, &c. 



Amoraese, ( am-o'me-5 ). [ Amomum, q.v. ] 

 = Ginger worts=Zingiberaceae. A sub-divi- 

 sion of Amomales. 



Amomum, (a-mo'mum). [Gk. amomos, spot- 

 less.] A plant belonging to Zingiberaceoc, 

 with white flowers; the type of Amomales. 



Amorphous, (a-mor'-fus). [Gk. a, not; mor- 

 phe, regular form.] Used of minerals that 

 are not crystalline, and therefore have no 

 regular and symmetrical form ; also used 

 generally for any substance having no defl- 

 nite form. 



Amorphozoa, ( am-or-f o-zo'a ). [Gk. a, not; 

 morphe, regular form; zoon, animal.] A gen- 

 eral term for animals having no definite 

 shape, such as sponges, &c. 



Ampelic acid, (am'pe-lik). [Ampelite, q.v.] 

 An acid obtained from bituminous shale. 



Ampelideae, (am-pe-lid'e-e). [Gk. ampelos, a 

 vine.]=Vitacese, q.v. A family of plants of 

 which the grape-vine is the type. 



Ampelin, (am'pe-lin). [Ampelite, q.v.] A 

 substance like kreosote, extracted from bitu- 

 minous shale. 



Ampelite, (am'pe-lit). [Gk., ampelos, a vine.] 

 =alum-slate, q.v. : named from being used 

 to kill vine parasites. 



Ampere's hypothesis of constitution of gases, 

 that at the same temperature and pressure a 

 given volume of any gas will always contain 

 the same number of molecules. A.'s theory 

 of magnetism, that every molecule of a body 

 when magnetised has an electric current 

 passing through it. 



Amphibia, (am-nb'i-a). [Gk. amphi, both ; 

 bios, life.]=Frogs, &c. : vertebrate animals 

 having gills when young, and when adult 

 usually both gills and lungs, sometimes lungs 

 only; so that when young they are water 

 animals, and when.adult can usually live on 

 either land or water: resemble higher verte- 

 brata in having limbs and red blood, but 

 differ inhavingno amnion or allantois: allied 

 to Ganoid fishes. 



Amphibians, (am-fib'i-anz). [Gk. amphi, both; 

 bios, life.]= Amphibia, q.v. 



Amphibichnites, ( am - fib- ik'nitz ). [ Am- 

 phibia, q.v. ; Gk. ichnos, footstep.] Fossil 

 footprints of amphibia. 



Amphibole, (am-fib'o-le). [Gk. amphibolos, 

 doubtful. ]=Hornblende = 5MgCaFeMuO,6Si 

 Ot>x(KCa)F;> amphibolite, a mineral easily 

 mistaken for augite=.Black schorl, a com- 

 plex silicate. 



Amphibole and Pyroxene group of minerals, 

 includes hornblende and other varieties of 

 Amphibole, and also augite and other varie- 

 ties of Pyroxene. 



Amphibrya, (am-fi-bri'a) == Endlicher's term 

 for Endogens, q.v. 



Amphiccelia, (am-fi-se'li-a). [Gk. amphi, both 

 sides; koilos, hollow.] Vertebrae that are bi- 

 concave, or have both surfaces hollow; as 

 in most fishes and some reptiles. 



Amphiccelous, (am-fi-se'lus). [Gk. amphi, 

 both sides; koilos, hollow.] Used to describe 

 vertebrae, both ends of which are concave. 



Amphicyon, (am-fik'i-on). [Gk. amphi, doubt; 

 kyon, dog.] A fossil quadruped, carnivorous, 

 and supposed to have some resemblance to a 

 dog; apparently intermediate between digiti- 

 grade and plantigrade animals. 



Amphidiscs, (am'fi-disks). [Gk. amphi, both 

 sides; diskos, quoit.] Spicula surrounding 

 the gemmules of Spongilla, resembling two 

 toothed wheels on one axle. 



Amphidotus=Heart-urchins; a variety of sea- 

 urchins=Spatangus, q.v. 



Amphigens, (am'fi-jenz). [Gk. amphi, both 

 sides; gennao, I grow.]=Amphigenie: plants 

 which grow in all directions; used by Brong- 

 niart for algae, fungi, and lichens =Thallo- 

 gens, q.v. 



Amphilestes, (am-fi-les't5z). A small animal 

 belonging to Mammalia, fossil remains of 

 which are found in the Stonesfield-slate rocks. 



Amphioxus, (am - fi - oks'us). [Gk. amphi, 

 double; oxus, pointed.] A fish, about 2 in. 

 long, having no brain, a simple heart, and a 

 respiratory system resembling that of a mol- 

 lusc; mistaken for a mollusc when first dis- 

 covered, and named Limax lanceolatus: in- 

 termediate between fishes and mollusca. Also 

 called Branchiostoma, Lancelot, and Phar- 

 yngobranchia. 



Amphipneusta, (ajn-fip-nu'sta). [Gk. amphi, 

 both ways; pneo, I breathe.]=Perennihran- 

 chiate amphibia: animals which retain their 

 gills in the adult state, such as the Proteus 

 and Siren. 



Amphipoda, (am-fip'o-da). [Gk. amphi, both 

 ways; podes, feet.] Crustacean animals hav- 

 ing sessile and immovable eyes, and append- 

 ages resembling feet (whence the name), 

 which serve for both walking and swimming. 



Amphiprostyle, (am-fi-pros'til.) [Gk. amphi, 

 both sides; prostyle, portico.] A rectangular 

 building, having a prostyle or portico at each 

 end, but no columns. 



Amphisbena, (am-fis-be'na). [Gk. amphis, 

 both ways; baino, I go.] A non-venomous 

 serpent, of nearly uniform thickness in body 

 and tail, found in tropical America arid East 

 Indies, able to move readily either way. 



AmphiscuXam-fis'si-I). [Gk. amphi, both ways; 

 skia, shadow, doubly shadowed.] Inhabit- 

 ants of the torrid zone, whose shadows are 

 sometimes to the north, and sometimes to 

 the south. 



Amphitheatre, (am-fi-the'a-ter). [Gk. amphi, 

 around; theatron, theatre.] A large building, 

 usually circular or elliptical, with seats, in 

 tiers, on a}l sides of it. 



