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as proper names, marking the plant, but bearing no other 

 significance. In the present case the second name, 

 impressa, is of use. The corolla of this plant has five small 

 impressions in the lower part, which marks it off clearly 

 from all its near relations. 



When we wish to refer to one kind of plant we call it a 

 species ; thus Epacris impressa is the name of a species, 

 and is distinct at least in our minds from the common 

 Rocket, Epacris lanuginosa. We commonly speak of a 

 species as if it was one clearly marked or rigid form. [n 

 that we are wrong; there is no such circumscribed species. 

 We can seize on one form, make it the type, and compare 

 others to it, and if they do not depart much from it we 

 say they belong to that species; but. after all, the species 

 is only a group of forms which we, for the sake of con- 

 venience, treat as one. If we raise fifty young from the 

 seed of a plant, no two are exactly alike; some may be 

 very similar, others not. If we raise more from the dis- 

 similar ones, we may soon produce forms very unlike the 

 original. This change may occur in nature, and may in 

 time become a fixed character; then it is only a matter 

 of opinion whether the new form shall be considered a dis- 

 tinct species. The name species is purely arbitrary ; it is 

 convenient and necessary, but has no absolute significance 

 in nature. The natural consequence is that botanists vary 

 in what they call species. Here we are calling several 

 forms one species, under the name Epacris impressa. The 

 most able local botanist we have had, Ronald Gunn, made 

 three species of it. Next generation a botanist may break 

 it up into a dozen. This is disheartening to the beginner, 

 who likes simplicity. He must blame nature, not the 

 botanist. 



When we find a group of species, the Wattles for 

 instance, which show such a great likeness in essential 

 features that we conclude they are close or recent off- 

 shoots from one type, we form another semi-natural group, 

 which we call a genus. In the same way we group genera 

 into families, and families into Orders. This brings all 

 known flowering plants into about forty-two large more 

 or less natural groups. These again are clearly divisible 

 into two classes, the Monocotyls, containing the Grasses, 

 Rushes, Lilies, Orchids, and such, and the Dicotyls, which 

 contains the rest. These two classes are very distinct, and 

 no proof has yet been brought forward that one is 

 descended from the other. 



