324 GLOSSARY. 



AS'TER-OID (Gr. aster, a star ; and eidos, form). Star-shaped, or possessing 



radiating lobes or rays like a star-fish. 

 AS-TE-ROID'E-A. An order of JScTiinodermata, comprising the Star-fishes, 



characterized by their rayed form. 



A-STOM'A-TOTJS (Gr. a, without; stoma, mouth). Not possessing a mouth. 

 AT'LAS (Gr. the god who holds up the heavens). The first vertebra of the neck, 



which" articulates with and supports the skull. 

 A'TRI-UM (Lat. for a hall). Applied to the great chamber or " cloa'ca," into 



which the intestine opens in the Tunicata. 

 AU-BEL'LA (Lat. aurum, gold)._ Applied to the chrysalides of some Lepidop- 



tera, on account of their exhibiting a golden lustre. 

 AU'RI-CLE (Lat. dim. of auris, ear). Applied to one of the cavities of the 



heart, by which blood is driven into the ventricle. 

 AU-TOPH'A-GI (Gr. autos, self; phago, I eat). Applied to birds whose young 



can run about and obtain food for themselves as soon as they escape from 



the egg. 



A'VES (Lat. avis, a bird). The class of the Birds. 

 AV-I-CU-LA'RI-TTM (Lat. avicula, dim. of avis, a bird). A singular appendage, 



often shaped like the head of a bird, found in many of the Polyzoa. 

 Axis (Gr. axon, a pivot). The second vertebra of the neck, upon which the 



skull and atlas usually rotate. 

 Az'y-eos (Gr. a, without; zugon, yoke). Single ; without a fellow. 



BAC-TE'RI-TTM (Gr. bakterion, a staff). A kind of staff-shaped filament which 

 appears in organic infusions after they have been exposed to the air. 



BAL'AN-CERS. 



BA-LAN'I-D^: (Gr. balanos. an acorn). A family of sessile Cirripedes, com- 

 monly called " Acorn-shells." 



BA-LEEN' (Lat. balcena, a whale). The horny plates which occupy the palate 

 of the true or " whale-bone " Whales. 



BAT'I-DES (Gr. batos, a bramble). The family of the Elasmobranchii, com- 

 prising the Kays. 



BA-TRA'CHI-A (Gr. batrachos, a frog). Often loosely applied to any of the 

 Amphibia, but sometimes restricted to the Amphibians as a class, or to the 

 single order of the Anoura. 



BI'FID (Lat. bis, twice ; findo, I cleave). Cleft into two parts ; forked. 



BI-LAT'ER-AL (Lat. bis, twice ; latus, a side). Having two symmetrical sides. 



BI-MA'NA (Lat. bis, twice ; manus, a hand). The order of Mammalia compris- 

 ing Man alone. 



BIP'E-DAL (Lat. bis, twice ; pes, foot). "Walking upon two legs. 



BI-RA'MOUS (Lat. bis, twice ; ramus, a branch). Applied to a limb which is 

 divided into two branches (e. g., the limbs of Cirripedes). 



BI'VALVE (Lat. bis, twice ; valvce, folding-doors). Composed of two plates or 

 valves ; applied to the shell or the Lamellibranchiata and Erachiopoda, and 

 of the carapace of certain Crustacea. 



BLAS-TOID'E-A (Gr. blastos, a bud ; and eidos, form). An extinct order of Echi- 

 nodermata, often called Pentremites. 



BRACH-I-OP'O-DA (Gr. brachion, an arm ; pous, the foot). A class of the Mol- 

 lu&coida, often called "Lamp-shells/' characterized by possessing two 

 fleshy arms continued from the sides of the mouth. 



BRA'CHI-UM (Gr. ~brachion, arm). Applied to the upper arm of Verte- 

 brates. 



BRACH-Y-U'RA (Gr. brachus, short ; oura, tail). A tribe of the Decapod Crus- 

 taceans with short tails (i. e., the Crabs). 



BRACTS. (See Hydrophyllia.) 



BRAD-Y-POD'I-DJE (Gr. bradus, slow ; podes, feet). The family of Edentata 

 comprising the Sloths. 



BRANCH'I-A ^Gr. bragrchia, the gills of fishes). A respiratory organ adapted to 

 breathe air dissolved in water. 



BRANCH' I-ATE. Possessing gills or branchiae. 



BRAN-OHIF'E-RA (Gr. bragchia, gills ; and phero, I carry). A division of Gas- 



