48 PLANTS OF NEW ZEALAND 



For ordinary field purposes, the venation is the most readily 

 available distinctive character, but the student will soon 

 recognise the differences between a mono- and a di- 

 cotyledon. The leaves of the monocotyledon are usually long 

 and narrow, and often sword-shaped. They frequently have 

 sheathing bases. The chief New Zealand monocotyledons are 

 the grasses, rushes, cut-grasses, bulrushes, native flax (Plwr- 

 mium), cabbage-tree, supple-jack, and Nikau-palm. The 

 dicotyledons constitute the great majority of flowering plants. 



The classes are sub-divided into sub-classes. The sub- 

 classes are split up into orders, the orders into families, the 

 families into genera, and the genera into species. The species 

 form the units on which the whole classification is built up. 

 It is impossible to define a species further, than by saying that 

 all plants of one kind^are included in it. All individuals within 

 the species, are more like each other than they are like 

 any plants outside of it. The species are built up into genera. 

 The genus may contain any number of species. Thus, there 

 is only one species of Entelea known, and it is confined to the 

 Auckland province. On the other hand, there are some eighty 

 species of Veronica in New Zealand, and many more in other 

 parts of the world. 



Every plant has two names : (1) the name of the genus to 

 which it belongs ; (2) the name of the species. Thus, there 

 are two kinds of native flax, each with the same generic name 

 (Phormium) but with different specific names, P. tenax and 

 P. CooJcianum. To the scientific name of the plant, should be 

 attached the name of the author of the species. This has not 

 been done here, as the names given in Mr. Cheeseman's hand- 

 book have been adopted, except in one or two specially 

 mentioned instances. 



In endeavouring to identify a species, the student should 

 remember that there is scarcely any rule in botany without 

 exceptions. Many of our New Zealand plants do not 

 completely exemplify the characters of the order, or genus, 



