OF GREAT BRITAIN 3 



A peltate leaf is one which has a stalk attached at ov near its centre, as 

 the Wall Pennywort (25). 



A perfoliate leaf is one through the centre of which a stalk passes, as in 

 Hare's Ear (26). 



Two leaves joined at their bases, and having a stem passing through them, 

 are termed connate, as in the Chlora or Yellow- wort (27). 



A leaf which clasps the stem at its base, like that of the Yellow-horned 

 Poppy, is termed amplexicaul. 



The margin of a leaf may be entire, as in the Soapwort (28) ; crenate, as 

 in Marsh Pennywort (29) ; serrate (saw-edged), as in Rose (30) ; toothed, as 

 in Enchanter's Nightshade (31); or fringed, as in Rock-rose (32). 



The terms employed in this volume to describe the forms of leaves are : — 



Hair-like ; as in AVater Crowfoot (33). 



Linear ; as in Grass. 



Strap-shaped ; as in Sand Strap wort (3i). 



Oblong ; as in Rock-rose (32). 



Elliptical ; oval, with both ends alike, as in the leaflets of Rose (30). 



Egg-shaped; oval, with the base broader than the extremity, as in Pear (35). 



Inversely egg-shaped ; oval, with the base narrower than the extremit}^, 

 as in 36. 



Rounded ; as in 37. 



Heart-shaped ; as in the Violet (38). 



Inversely heart-shaped; as in the leaflets of Medick (18). 



Kidney-shaped ; as in Ground Ivy (39). 



Arrow-shaped ; as in Arrow-head (40). 



Halbert-shaped ; arrow-shaped, Avith the barbs turned outwards, as in the 

 Common Pink Bindweed. 



Angular ; as in Ivy (41). 



Sworcl-shaped ; as in Flag (42). 



Stipules : two little wing-like pieces often seen at the base of the leaf- 

 stalk, as in the Rose (43) and the Vetches. In the former, the stipule is 

 oblong ; in the latter, it is often arrow-shaped. 



Bracts are the small leaves often situated beneath the flower, as in the 

 Broom Rape (44). When several of these floral leaves grow in a whorl, they 

 form what is termed an involucre (47). In plants of the Umbelliferous tribe, 

 they often grow at the base of the general and partial umbels, as in 

 figure 46 ; and in Compound flowers, as the Dandelion, they are numerous 

 at the base of the heads of flowers. In this flower they are more like scales 

 than small leaves. 



The Flower. The Calyx, or flower-cup. This enfolds the bud before 

 fully blown, and generally afterwards surrounds the blossom. It is usually 

 green, and its several leaves are termed sepals (45). Sometimes the sepals 

 unite at the base, forming a true cup, but the calyx A'aries much in form. 

 When composed of two distinct lobes, one of which overhangs the other, 

 it is termed gaping : in some cases it is double (48) ; and in the Composite 

 and some other flowers, it is at first a mere ring, which ultimately becomes 

 the pappus or down (49). 



The Corolla. This is the brightly tinted portion of the flower, which is 



1—2 



