GLOSSARY. 377 



Transverse — Crosswise. 



Trenchant — Compressed to a sharp edge. 



Truncate — Abrupt, as if cut squarely off. 



Tubercle — A small excrescence, like a pimple. 



Tympanum — Drum of the ear ; external in some Batracnia. 



Typical — Of a structure the most usual in a given group. 



Ulna — The inner or posterior bone of the fore-arm. 



Ungulate — Provided with hoofs. 



Unguiculate — Provided with claws. 



Unicolor — Of a single color. 



Urosteges — The plates underneath the tail of a serpent. 



Vent — The external opening ot the alimentary canal. 



Ventral — Pertaining to the abdomen. 



Ventral fins — The paired fins behind or below the pectoral fins 



in fishes, corresponding to the posterior limbs in die higher 



vertebrates. 

 Ventral plates — Gastrosteges in serpents. 

 Ventricle — One of the chambers of the heart. 

 Versatile — Capable of being turned -either way. 

 Vertebra — One of the bones of the spine. 

 Vertical — Up and down. 

 Vertical fins — The fins on the median line of the body; the dorsal, 



anal and caudal fins. 

 Vertical plate — Central plate on the head of a serpent. 

 Villiform — Said of the teeth of fishes when slender and crowded 



into velvety bands. 

 Viscous — Slimy; viscid. 

 Vitta — A band of color. 

 Viviparous — Bringing forth living young. 

 Vomer — In fishes, the front part of the roof of the mouth ; a bone 



lying immediately behind the premaxillaries. 

 Web — The vane of a feather, on either side of the rhachis or 



" stem " ; also, the membrane connecting the toes. 

 Zygodactyle— Yoke-toed; having the toes in pairs — two in front, 



tw^o behind. 

 Zygoma — The malar or cheek bone. 



