GLOSSARY. 321 



Tarsus (pi. Tarsi). — The jointed feet of articulate animals, such as 

 Insects. 



Teleostean Fishes. — Fishes of the kind familiar to us in the 

 present day, having the skeleton usually completely ossified and 

 the scales horny. 



Tentacula or Tentaci.es. — Delicate fleshy organs of prehension or 

 touch possessed by many of the lower animals. 



Tertiary. — The latest geological epoch, immediately preceding the 

 establishment of the present order of things. 



Trachea. — The windpipe or passage for the admission of air to the 

 lungs. 



Tridacttle. — Three-fingered, or composed of three movable parts 

 attached to a common base. 



Trilobites. — A peculiar group of extinct Crustaceans, somewhat 

 resembling the Woodlice in external form, and, like some of 

 them, capable of rolling themselves up into a ball. Their 

 remains are found only in the Palasozoic rocks, and most abun- 

 dantly in those of Silurian age. 



Trimorphic. — Presenting three distinct forms. 



Umbellifer^:. — An order of plants in which the flowers, which 

 contain five stamens and a pistil with two styles, are supported 

 upon footstalks which spring from the top of the flower stem 

 and spread out like the wires of an umbrella, so as to bring all 

 the flowers in the same head (umbel) nearly to the same level. 

 (Examples, Parsley and Carrot.) 



Ungulata. — Hoofed quadrupeds. 



Unicellular. — Consisting of a single cell. 



Y a scular. — Containing blood-vessels. 



Vermiform. — Like a worm. 



Yertebrata : or Vertebrate Animals. — The highest division of 

 the animal kingdom, so called from the presence in most 

 cases of a backbone composed of numerous joints or vertebrae, 

 which constitutes the centre of the skeleton and at the same 

 time supports and protects the central parts of the nervous 

 system. 



Whorls. — The circles or spiral lines in which the parts of plants are 



arranged upon the axis of growth. 

 Workers. — See Neuters. 



