GLOSSARY. 381 



Akctocton (Gr, arctos, bear ; kuon, dog). An extinct genus of Carnivora. 



Arenaceous. Sandy, or composed of grains of sand. 



Arenicolites (Lat. arena, sand ; colo, I inhabit). A genus founded on bur- 

 rows supposed- to be formed by worms resembling the living Lobworms 

 {Areyiicola). 



Articulata (Lat. articulus, a joint). A division of the animal kingdom, com- 

 prising Insects, Centipedes, Spiders, and Crustaceans, characterised by the 

 possession of jointed bodies or jointed limbs. The term Arthropoda is now 

 more usually employed. 



Artiodacttla (Gr. artios, even ; daktulos, a finger or toe). A division of the 

 hoofed quadrupeds ( Uiigulata.) in which each foot has an even number of 

 toes (two or four). 



AsAPHUS (Gr. asaphes, obscure). A genus of Trilobites. 



Ascoceras (Gr. askos, a leather bottle ; keras, horn). A genus of Tetrabran- 

 chiate Cephalopods. 



Asiphonate. Not possessing a respiratory tube or siphon. (Applied to a 

 division of the Lamellibranchiate Molluscs.) 



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

 radiating lobes or rays dike a star-fish. 



Asteroidea. An order of Echinodermata, comprising the Star-fishes, charac- 

 terised by their rayed form. 



AsTEROPHYLLiTES (Gr. oster, a star ; phullon, leaf). A genus of Palseozoic 

 plants, with leaves in whorls. 



AsTR^iD^ (Gr. Astrcea, a proper name). The family of the Star-corals. 



AsTYLOSPOXGiA (Gr. a, "without ; stulos, a column ; spoggos, a sponge), A 

 genus of Silurian Sponges. 



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



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



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



A^TCULA (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 ; zo^, life). Destitute of traces of living beings. 



Baculites (Lat. haculum, a staff). A genus of the Ammomtidoi. 



Bal^na (Lat. a whale). The genus of the Whalebone Whales. 



BALAXiDiE (Gr. balanos, an acorn). A family of sessile Cirripedes, commonly 

 called " Acorn-shells." 



Batrachia (Gr. batrachos, a frog). Often loosely applied to any of the Am- 

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

 single order of the Anoura. 



Belemnitid^ (Gr. beleinnon, a dart). An extinct group of Dibranchiate Ceph- 

 alopods, comprising the Belemnites and their allies. 



Belemnoteuthis (Gr. belemnon, a dart ; ieuthis, a cuttle-fish). A genus allied 

 to the Belemnites proper. 



Belinurus (Gr. belos, a dart ; oura, tail). A genus of fossil King-crabs. 



Beli.erophon (Gr. proper name). A genus of oceanic Univalves {He 



Belotetjthis (Gr. belos, a dart ; teuthis, a cuttle-fish). An extinct genus of 

 Dibranchiate Cephalopods. 



Beyrichia (named after Prof. Beyrich). A genus of Ostracode Crustaceans. 



Bilateral. Having two symmetrical sides. 



BiMANA (Lat. bis, twice ; manus, a hand). The order of Mammalia compris- 

 ing man alone. 



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



Bivalve (Lat. bis, twice ; valvoe, folding-doors). Composed of two plates or 

 valves ; applied to the shell of the La'^nellibranchiata and Brachiopoda, and 

 to the carapace of certain Crustacea. 



Blastoidea (Gr. Uastos, a bud ; and eidos, form). An extinct order of Echi- 

 nodermata., often called Pentremites. 



BPvACHIOPODA (Gr. hra,chion, an arm ; pous, the foot). A class of the Mollus- 



