FISH OF ONTARIO. Ill 



G. 



Ganglion. A nerve centre. 



Ganoid. Scales or plates of bone covered by enamel. 



Gape. Opening- of the mouth, 



Gastrosteges. Band-like plates along the belly of a serpent ; ventral 



plates. 

 Gibbous. Swollen ; protuberant. 



Gills. Organs for breathing the air contained in water. 

 Gill-arches. The bony arches to which the gills are attached. 

 Gill-openings. Openings leading to or from the branchiae. 

 Gillrakers. A series of bony appendages variously formed along the inner 



edge of the anterior gill arch. 

 Glabrous. Smooth. 

 Glossohyal. The tongue bone. 

 Gonys. The middle line of the lower mandible. 

 Gorget. Throat patch of peculiar feathers. 

 Graduated (spines). Progressively longer backward ; the third being as 



much longer than secrnd as second is longer than first. 

 Graduated (tail). One in which the outer feathers are regularly shorter 



from the middle. 

 Granulate. Rough with small prominences. 

 Gular. Pertaining to the upper fore-neck. 

 Guttate. Having drop-shaped spots. 



H. 



Haemal arch. An arch under a haemal spine for the passag-e of a blood- 

 vessel. 



HcKmal canal. The se' ies of haemal arches as a whole. 



Haemal spine. The lowermost spine of a caudal vertebra, in fishes. 



Haemopophyses. Appendages on the lower side of abdominal vertebrae in 

 fishes. 



Hallux. The great toe — in birds the hind toe. 



Height. Vertical diameter. 



Heterocercal. Said of the tail of a fish when unequal — the backbone evi- 

 dently running into the upper lobe. 



Hirsute. With shaggy hairs. 



Homocercal. Said of the tail of a fish when not evidently unequal ; the 

 backbone apparently stopping at the middle of the base of the 

 caudal fin. 



Humerus. Bone of the upper arm. 



Hyoid. Pertaining to the tongue. 



Hyoid apparatus. Formed by a series of bones extending along the inner 

 side of the mandible and supporting the tongue. 



