14 GLOSSARY. 



A'ves (L. birds). One of the divisions of the Vertcbrata. 

 Avicula'rium (L. avicula, a little bird). An appendage of the 



Polyzoa which somewhat resembles a bird's head. 

 Ax'ial. A term applied to that part of the skeleton which 



forms the main axis of the body. 

 Axilla (L. the arm-pit). The angle made by the leaf of a 



plant with the stem. Used also in human anatomy in its 



literal signification, to denote the angle between the arm 



and the trunk. 

 Axis (L. a pivot). The second cervical vertebra, which suj>- 



plies the pivot on which the head turns. Also applied to 



the central portion of the body round which the other 



parts are arranged. 

 A'zygos u'vulae (Gr a, not ; zugos, a yoke). A'muscle of the 



uvula. The term azygos is used as an adjective, to denote 



a muscle, vein, or other part of the body which is without 



a fellow. 



Bacil'lary (L. lacillum, a little staff). Applied to the layer of 

 the retina which contains the rods and cones. 



Bacillus (L. bacillum, a little staff). A variety of Bacterium. 



Bacte'rium (Gr. bakterion, a staff). The rod-like jointed filament 

 which is found in putrefying organic infusions. 



Baguette (Fr. baguette, a small stick, a ramrod). The term 

 applied to the curved rods contained in the capsules into 

 which the nucleolus of some Infusoria divides during con- 

 jugation. 



Balaenoi'dea (L. bal&na, a whale). A division of the Cctacea, 

 comprising the right whale and the fin-fishes. 



Balan'idae (Gr. balanos, an acorn). The sessile Cirripedia. 



Baleen (Vr. ba/eine, , whalebone). The whalebone plates which 

 in the Balaenoidea take the place of teeth. 



Earb (L. barba, a beard). The term applied to the lateral 

 processes of the rachis of the contour feathers of a bird. 



Bar'bule (L. dim. of barba, a beard). Pointed processes of 

 the barbs of the contour feathers of a bird. 



Basalia (Gr. basis, a pedestal). The basal cartilages of the fins 

 of the Elasmcbrjnchii. 



Basic'erite (Gr. basis, a pedestal ; keraia, a horn). The second 

 joint of the antennae of Crustaceans. 



