GLOSSARY 



Glochidium, pi. -a, the larva of a Fresh- 

 water Mussel. 



Glottis (the Greek name), the opening- of the 

 windpipe in the floor of the pharynx. 



Gonophore (Gk. gontis, offspring-; ph%ro, I 

 bear), in Zoophytes, a bud in which egg- 

 cells or sperms are produced. 



Green glands. See Ant ennary gland. 



Grey matter, that part of the central nervous 

 system made up largely of nerve-cells. 



Ground- Pearl, in some Scale-Insects, the en- 

 cysted underground pupa. 



Gular (L. gula, the throat), near the throat. 



Gut, the digestive tube or alimentary canal. 



Haemoglobin (Gk. haima, blood; globin, a 

 kind of albuminoid), a complex substance to 

 which red corpuscles owe their colour, and 

 which in some animals may be dissolved in 

 the blood-plasma. Acts as an oxygen- 

 carrier. 



Halteres (L. for club-shaped weights used by 

 gymnasts). See Balancers. 



Haptic (Gk. haptiktis, endowed with the sense 

 of touch), used of sensations of contact. 



Herbivorous, plant-eating-. 



Heredity, the transmission of characters from 

 one g-eneration to another. 



Heterocercal (Gk. hMros, diverse; kZrkos, 

 tail), unsymmetrical. Used of the tail-fin of 

 certain Fishes, e.g. Sharks. 



Heterodactylous (Gk. ht&rtfs, different; dak- 

 tyltis, a toe), in the feet of some climbing- 

 Birds, with the first and second toes turned 

 back, while the third and fourth are directed 

 forwards. 



Hind-gut, the hinder part of the dig-estive 

 tube, developed as an inpushing- from the 

 exterior. 



Hip-girdle, the skeleton of the hip-region. 



Histology (Gk. histtis, a texture; Itigos, a dis- 

 course), or Minute anatomy, the study of 

 structure by means of the compound micro- 

 scope. 



Hock, in hind-limb of Horse, &c., the ankle. 



Holarctic (Gk. holos, all; arkttfs, the north), 

 native to the colder parts of the Northern 

 Hemisphere. 



Homocercal (Gk. hbmtis, like; kerktis, a tail), 

 applied to the lobed and externally sym- 

 metrical tail of ordinary Fishes. 



Homologous, displaying homology. 



Homology (Gk. htimoltigos, agreeing), applied 

 to parts which resemble one another as re- 

 gards relative position and mode of develop- 

 ment, irrespective of use or function. Serial 

 homology, agreement between structures 

 forming- a series, e.g. spinal nerves. See 

 also Analogy. 



Honey-comb stomach. See Reticulum. 



Host, an organism on which a parasite preys. 

 See Parasitism. 



Humeral, related to the upper arm. 

 VOL. IV. 



Humerus (the Latin name), the upper-arm 



bone. 

 Hybernation, the habit of passing into a torpid 



state during- the cold or dry season. 

 Hybrid (L. hybrida, a cross-bred animal), a 



cross between two distinct species. Hybrids 



are usually sterile. 

 Hydroid Zoophytes, colonial Ccelenterates 



which in fixed stage superficially resemble 



sea-weeds. 

 Hyoid bone, supports root of tong-ue in higher 



Vertebrates. 

 Hyomandibular, related to the first two 



visceral arches (which see), respectively 



known as mandibular and hyoid. 



Ilium, the dorsal element of the hip-girdle. 



Imago, pi. -ines (L. for fig-ure, portrait, or 

 statue), in Insects, the adult stage. 



Incisor, one of the front teeth of a Mammal. 

 Next to these are the Canines. See Canine. 



Inhalent. See Siphon. 



Insertion of a muscle, the end attached to 

 a relatively movable part. 



Instinct, the power of performing 1 complex 

 actions, subserving adjustment to surround- 

 ings, independently of experience or instruc- 

 tion. 



Integropalliate, in the shell of a Bivalve Mol- 

 lusc, with continuous pallial line. 

 Intelligence, the ability to profit by experience 



in adjusting behaviour to changing surround- 

 ings. 

 Interambulacral area, in Echinoderms, a band 



or zone which does not bear tube-feet. 

 Inter - clavicle, a skeletal element situated 



between the clavicles in some animals. 

 Intermedium, a proximal median element in 



the carpus or tarsus. 

 Interradial, in radially symmetrical animals, 



relating to an interradius. 

 Interradius, in radially symmetrical animals, 



a region of the body coming between two of 



the radii. 

 Invertebrate, devoid of a backbone or its 



equivalent. 

 Iris (L. for rainbow), the coloured part of the 



eye, serving as a diaphragm external to the 



lens. Its opening is the pupil. 

 Ischium, the ventral and posterior element of 



the hip-girdle. 

 Isinglass, a fine kind of gelatine, prepared 



from the swim-bladders of fishes, especially 



sturgeons. 



Joint-gill, in Crustaceans, a gill attached to 

 the joint at the base of a limb. 



Kainozoic epoch, (Gk. kaintfs, recent; zoe, 



life), the latest geological era. 

 Katabolic, relating to katabolism. 

 Katabolism (Gk. katabole, a casting down), 



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