GLOSSARY 



497 



Caecum, pi. -a (L. ccecus, blind), a blindly 

 ending" tube. 



Calcaneum (L. for heel), the heel-bone. 



Calcar (L. for spur), a small pointed projection 

 on the inner side of a Frog's hind-foot. 



Calcareous (L. calx, calcis, lime), of a limy 

 nature. 



Callosity, a hardened patch of skin. 



Calyx (Gk. kalyx, a cup), the outer investing 

 leaves of a flower. 



Canine, one of the four " eye-teeth " in a Mam- 

 mal. Situated outside the Incisors(which see), 

 and well developed in carnivorous forms. 



Cannon-bone: (i) in Horse, &c., the large 

 metacarpal or metatarsal of the single 

 digit; (2) in Ruminants, the compound bone 

 formed by fusion of third and fourth meta- 

 carpals or metatarsals. 



Capillaries (L. capillus, hair), microscopic 

 blood-vessels with exceedingly thin walls. 

 The name is misleading, since they are much 

 smaller than the finest hairs. 



Carapace, a firm protective shield covering the 

 upper side and flanks in some animals. 



Cardia (the Greek name), the opening be- 

 tween gullet and stomach. 



Cardo (L. for hinge), the basal joint of an 

 Insect's second jaw. 



Carinate (L. carina, a keel): (i) with a keel- 

 like projection; (2) applied to flying birds, in 

 which the breast-bone possesses such a pro- 

 jection, for the attachment of the muscles of 

 flight. 



Carnassials (L. carnosus, relating to flesh), or 

 Flesh-teeth, in Carnivores, four cutting 

 cheek-teeth which act like scissors. 



Carnivorous, flesh-eating. 



Carotid (Gk. k&ra, the head), a term applied to 

 arteries which carry blood to the head and 

 neck. 



Carpale, pi. --ia (Gk. karptis, the wrist), the 

 distal elements of the carpus. 



Carpel (Gk. karptis, fruit), a modified flower- 

 leaf that bears ovules. The Pistil (which 

 see) consists of one or more carpels. 



Carpus (Gk. karptis, the wrist), the skeleton of 

 the wrist. 



Cartilage, gristle. 



Caste, in social Insects, a set of similar indi- 

 viduals. 



Caval veins, in air-breathing Vertebrates, the 

 great veins which return impure blood to the 

 heart. 



Caviare, the preserved hard roes (ovaries) of 

 the sturgeon. 



Cell, a nucleated mass of protoplasm, gener- 

 ally microscopic, and usually regarded as 

 the unit of structure. 



Centrale, a central element of the carpus or 

 tarsus. 



Centrum, pi. -a, of a vertebra, the relatively 

 massive ventral part, flooring the hole tra- 

 versed by the spinal cord. 



Cephalo- thorax (Gk. ktphale, the head ; ihorax, 



the chest), in some Arthropods, the front 

 region of the body, formed by fusion of the 

 head with part or all of the thorax. 



Cerata (Gk. ke'rata, horns), in Sea-slugs (Nudi- 

 branchs), club-shaped outgrowths springing 

 from the back. 



Cercaria, pi. -ae (Gk. k&rktfs, a tail), in Flukes, 

 a tadpole-shaped stage in the life-history. 

 Produced by the Redia (which see), and 

 immediately preceding the adult stage. 



Cerci (Gk. kVrktis, a tail), jointed rods project- 

 ing from the hinder end of an Insect's abdo- 

 men. 



Cere (L. cera, wax), a bare patch of skin at 

 the base of a Bird's beak. 



Cerebellum (L. dim. of cerebrum, the brain), 

 an unpaired dorsal outgrowth from the 

 hinder part of the brain of a Vertebrate. 



Cerebral hemispheres (L. cerebrum, the brain), 

 the highest part of the brain in Vertebrates, 

 usually consisting of a pair of outgrowths 

 from near its front end. 



Cervical (L. cervix, the neck), relating to the 

 neck. 



Chalaza (Gk. for hail), in a Bird's egg, a 

 twisted cord-like structure traversing the 

 albumen (" white ") at either end. 



Cheek-teeth, the back-teeth. 



Chelicera, pi. -ae, (Gk. chele, a claw; kVras, a 

 horn), one of the first pair of head-limbs in 

 Spider-like animals (Arachnida). 



Chlorophyll (Gk. chlortis, grass green ; phylltin, 

 a leaf), or Leaf-green, the characteristic pig- 

 ment of green plants. It also occurs in a 

 few lower animals. 



Chordotonal organ (Gk. chtirde, a string; 

 tonaios, stretched), in some Insects, a kind of 

 sense-organ related to balance, or hearing, 

 or both. 



Choroid (Gk. choritin, skin ; eidtis, appearance), 

 the middle coat of the eyeball. It is pig- 

 mented and vascular, and externally forms 

 the iris (which see). 



Chromatophore(Gk. chroma, colouring matter; 

 phVrd, I bear), a small or minute body con- 

 taining pigment, and situated in the skin. 

 Colour-changes are due to the alteration in 

 size of such bodies. 



Chrysalis, pi. -ides (the Greek name), the 

 pupa of a Moth or Butterfly. 



Ciliary action, the movement of cilia. 



Cilium, pi. cilia (L. cilium, eyelash), a micro- 

 scopic thread of protoplasm, possessing the 

 power of alternately bending and straighten- 

 ing. Numerous cilia are usually associated 

 together. The derivation is misleading. 



Circulatory organs, the structures concerned 

 with distributing blood and lymph through- 

 out the body. 



Cirrus, pi. -i (L. cirrus, a tentacle): (i) one of 

 the slender-jointed appendages of a Barnacle; 

 (2) one of the sensory filaments borne by the 

 segments of Bristle-Worms ; (3) in Sea-Lilies, 

 one of the jointed threads of which numerous 

 circlets are borne by the stalk. 



