396 GLOSSARY 



ASTEROID (Gr. aster, a star; and eidos, form). Star-shaped, or 

 possessing radiating lobes or rays like a star-fish. 



ASTEROIDEA. An order of Echinodermata, comprising the Star- 

 fishes, characterized by their rayed form. 



ASTEROPHYLLITES (Gr. aster, a star; phullon, leaf). A genus of 

 Palaeozoic plants, with leaves in whorls. 



ASTRJEIVJE (Gr. Astros, a proper name). The family of the 

 Star-corals. 



ASTYLOSPONGIA (Gr. a, without; stulos, a column; spoggos, a 

 sponge). A genus of Silurian Sponges. 



ATHYRIS (Gr. a, without; thura, door). A genus of Brachiopods. 



ATRYPA (Gr. a, without; trupa, a hole). A genus of Brachiopods. 



AVES (Lat. avis, a bird). The class of the Birds. 



AVICULA (Lat. a little bird). The genus of Bivalve Molluscs 

 comprising the Pearl-oysters. 



AXOPHYLLUM (Gr. axon, a pivot; phullon, a leaf). A genus of 

 Rugose Corals. 



Azoic (Gr. a, without; zoe, life). Destitute of traces of living 

 beings. 



B 



BACULITES (Lat. baculum, a staff). A genus of the Ammoni- 

 tid<z. 



BAL^NA (Lat. a whale). The genus of the Whalebone Whales. 



BALANID.E (Gr. balanos, an acorn). A family of sessile Cirri- 

 pedes, commonly called " Acorn-shells. " 



BATRACHIA (Gr. batrachos, a frog). Often loosely applied to 

 any of the Amphibia, but sometimes restricted to the Am- 

 phibians as a class, or to the single order of the Anoura, 



BELEMNITHLE (Gr. belemnon, a dart). An extinct group of 

 Dibranchiate Cephalopods, comprising the Belemnites and 

 their allies. 



BELEMNOTEUTHIS (Gr. belemnon, a dart; teuthis, a cuttle-fish). 

 A genus allied to the Belemnites proper. 



BELINURUS (Gr. belos, a dart; our a, tail). A genus of fossil 

 King-crabs. 



BELLEROPHON (Gr. proper name). A genus of oceanic Uni- 

 valves (Heteropoda}. 



BELOTEUTHIS (Gr. belos, a dart; teuthis, a cuttle-fish). An ex- 

 tinct genus of Dibranchiate Cephalopods. 



BEYRICHIA (named after Prof. Beyrich). A genus of Ostra- 

 code Crustaceans. 



BILATERAL. Having two symmetrical sides. 



BIMANA (Lat. bis, twice; manus, a hand). The order of Mam- 

 malia comprising man alone. 



BIPEDAL (Lat. bis, twice; pes, foot). Walking upon two legs. 



BIVALVE (Lat. bis, twice valves, folding-doors). Composed of 

 two plates or valves; applied to the shell of the Lamellibran- 

 chiata and Brachiopoda, and to the carapace of certain Crus- 

 tacea. 



BLASTOIDEA (Gr. blastos, a bud; and eidos, form). An extinct 

 order of Echinodermata, often called Pentremites. 



