256 



HUTCHINSON'S POPULAE BOTANY 



pinnate because there is an odd lobe at the extremity. * The leaflets 

 themselves are net-veined, the large central vein in each being known as the 

 midrib ; their shapes are broadly elliptical, and their sharp, saw-like margins 

 are serrate (Lat. serratus, saw-like). The portion of the leaf-stalk at the base 

 of the leaf is the petiole (Lat. petiolus, a little foot) ; but beyond the first pair 



of leaflets it is called the 

 rachis (Greek rachis, the 

 spine). The two small 

 leaf-like organs at the base 

 of the petiole are stipules 

 (Lat. stipula, a blade). 



Now, all this is very be- 

 wild e r i n g ; nevertheless, 

 a few walks in the country, 

 if the neighbourhood be 

 at all favourable for botan- 

 izing, will soon familiarize 

 one with the principal 

 leaf-forms, and more will 

 probably be learnt in a 

 single hour thus spent 

 (with text-book in hand 

 for reference) than in five 

 or six hours of wearying 

 desk-work. There is a 

 spot which we could men- 

 tion, not twenty miles from 

 London, which is peculiar- 

 ly adapted for this purpose. 

 It is a charming piece of 

 Surrey landscape, in his 

 lifetime a favourite spot 

 with that prince of Nature- 

 interpreters, Richard 

 Jefferies ; so we will trans- 

 port ourselves thither in 

 imagination, and saunter 

 together down the shady lane, not yet disfigured by lamp-post or flaming 



FIG. 313. FIVE-RANKED (PENTASTICHOUS) ARRANGE- 

 MENT OF LEAVES OF THE CHERRY. 



* Compound leaves which have no such terminal lobe, but all the leaflets of which 

 run in pairs (fig. 315), are described as par i- pinnate (Lat. par, paris, equal, and pinnatus). 

 We get this form in the Vetches ( Vicia). In many of the Acacias each of the pinnae of the 

 pinnate leaves is itself pinnate, so that the form is doubly or li-pinnate ; while in the Lesser 

 Meadow-rue (Thalictrum minus) the division is carried a step further, and we have a tri- 

 pinnate form. 



