49 6 



GLOSSARY 



Antler-royal, the third branch of a Red Deer's 

 antler (counting- from its base). 



Aorta (Gk. aeiro, I carry), the chief artery of 

 the body. 



Aortic arches, the arteries which traverse the 

 visceral arches of Vertebrates. 



Apical disc, in Echinoderms (especially sea- 

 urchins), a double circlet of plates on the 

 upper surface of the body. 



Apiculture (L. apis, a bee), bee-culture. 



Apteria (Gk. a, without; pterylon a feather), 

 featherless patches of a Bird's skin. 



Arch, of a vertebra (or joint of the backbone), 

 the dorsal part which forms the roof and 

 sides of the hole traversed by the spinal 

 cord. 



Archenteron (Gk. arche, a beginning 1 ; enteron, 

 an intestine), the digestive cavity of the 

 Gastrula (which see). 



Area of distribution, area inhabited by a 

 species or other animal group. It is discon- 

 tinuous if consisting of two or more isolated 

 portions. 



Artery, a blood-vessel which carries blood 

 from the heart. 



Articular processes, projections on the arches 

 of vertebrae, by which these are connected 

 tog-ether. 



Artificial selection, the production of breeds 

 of domesticated animals by human ag-ency. 



Assimilation (L. adsimilo, I make like), the 

 conversion of digested food into body-sub- 

 stance. 



Atavism (L. atavus, an ancestor). See Re-ver- 

 sion. 



Atlas, the ring- -shaped first vertebra of the 

 neck-region. 



Atoll, a ring--shaped coral island. 



Atrial cavity (L. atrium, a hall), a space sur- 

 rounding- most of the pharynx in Lancelets 

 and Ascidians. 



Atriopore, the opening of the Atrial cavity 

 (which see). 



Auricle (L. auricula, a little ear), a relatively 

 thin-walled heart-chamber, into which veins 

 pour blood. 



Auricularia, pi. -ae (L. for lobe of the ear), in 

 Sea-Cucumbers, a bilateral larva, provided 

 with a sinuous ciliated band, sug-gesting- the 

 appearance of an ear in side-view. 



Australian region, Australia and adjacent 

 islands, with eastern part of East Indies, 

 New Zealand, and Polynesia. 



Axis, the second neck-vertebra. 



Balancers (halteres), small club-shaped struc- 

 tures representing the reduced hind-wings in 

 Flies. 



Baleen ("whalebone"), in toothless Whales, 

 elastic plates hanging- down from the roof 

 of the mouth. 



Barb, one of the flattened branches borne by 

 the axis of a feather. 



Barbel, one of the sensitive filaments with 



which the mouth-region is provided in some 

 Fishes, e.g. Cat-Fishes. 



Barbule, one of the small branches borne by 

 the barbs of a feather. 



Bastard-wing (ala spuria), a tuft of feathers 

 borne by the thumb of a bird. 



Beche-de-mer, Trepang (which see). 



Bedeguar, a tufted gall on the rose, produced 

 by the attack of a Gall-Fly. 



Beneficials, those wild animals that by their 

 habits promote the welfare of mankind. 



Benthos (Gk. benthos, depth), the assemblage 

 of anjmals inhabiting deep water. 



Bez-tine, the second branch of a Red Deer's 

 antler (counting- from its base). 



Biconcave, hollow on both sides, e.g. the ver- 

 tebra of a Fish. 



Bicuspid. See Premolar. 



Bilateral Symmetry. See Symmetry. 



Bile, or Gall, the secretion of the liver. 



Bile-duct, a tube throug-h which bile passes 

 into the intestine. 



Biology (Gk. bib's, life ; Ibgos, a discourse), the 

 science of life. 



Bipinnaria, pi. -ae, in Star-Fishes, the bilateral 

 larva, which is provided with pairs of soft 

 ciliated arms. 



Bivalve, applied to the shell of a Mollusc when 

 made up of two pieces or valves, e.g. in a 

 Mussel. Lamp-shells (Brachiopoda) are also 

 bivalve, and Mussel -Shrimps (Ostracoda) 

 possess a bivalve shield or shell. 



Blastopore (Gk. blastbs, a g-erm ; ptira, a pas- 

 sage), the mouth of a Gastrula (which see). 



Blastosphere (Gk. blastbs, a g-erm; sphaira, 

 a sphere), a hollow and spheroidal kind of 

 Blastula (which see). 



Blastula (Gk. dim. of blastbs, a germ), the 

 embryonic stage resulting from Cleavage 

 (which see). 



Blight, a disease of plants, often due to the 

 presence of aphides. 



Blubber, in marine Mammals, a thick layer of 

 fat below the skin. 



Body - cavity, in animals higher than Zoo - 

 phytes, a space or series of spaces between 

 the internal organs and body-wall. 



Botany (Gk. botane, a plant), the science deal- 

 ing with plants. 



Bouchot, in mussel-culture, a collector made 

 of stakes with interwoven twigs. 



Brachiolaria, pi. -ae, a variety of the Bipin- 

 naria (which see). 



Bronchus, pi. -i, one of the two main branches 

 of the wind-pipe. 



Brood -parasitism, used of animals (e.g. the 

 Cuckoo) which evade the responsibility of 

 bringing up their own young. 



Brow-tine, the lowest branch of a Red Deer's 

 antler, projecting over the forehead. 



Byssus (Gk. byssos), adhesive threads by which 

 some Bivalve Molluscs attach themselves. 



