L : V*>:V LTHK-BOOK OF NATURE STUDY 



white flowers. It is a perennial plant, and all the parts above 

 ground die down in the autumn. Growth is, however, rapid 

 in the early summer months, so that the fully grown plant is 

 usually three to six feet high. 



If a plant is dug up and the underground parts freed from 

 the soil the green leafy shoot will be found to have arisen from a 

 thick brown underground stem of rather irregular shape. The 

 surface of this is marked with narrow scars left by scale-leaves, 

 and a little examination will throw light on the mode of growth 

 of the plant. The leafy shoot grows straight up from the thin 

 anterior portion of the underground stem, and appears to be the 

 development of the apex of the latter. In the axil of a scale- 

 leaf at the base of the shoot is a large bud, which is destined to 

 grow into next year's shoot. On looking at the older portion 

 of the underground stem we recognise the large circular scars 

 left by the aerial stem at the end of each annual joint or segment, 

 further growth having always been carried on by a lateral bud. 

 A number of thick roots grow out from the underground stem, 

 and the latter increases in thickness, its tissues serving as a place 

 of storage for reserve food material. This is used in the earlier 

 stages of the growth of the leafy shoots. The Cow-Parsnip is 

 thus a perennial herb, the leafy shoots of which die down each 

 autumn, leaving the old underground stem and the bud which 

 continues the growth next season. When more than one bud is 

 established the underground stem becomes branched, and more 

 than one leafy shoot is sent up from it each year. 



The leafy shoot consists of a short stem bearing a number of 

 large foliage-leaves, and branching above in the region bearing the 

 inflorescences. The stem is green, marked by numerous ridges, 

 and covered with coarse hairs. The internodes have a central 

 hollow, which is shown on cutting the stem across, but the nodes 

 are solid. Each leaf consists of a large leaf-sheath which sur- 

 rounds the stem almost completely, of a leaf-stalk and of a 

 branched or compound leaf-blade, composed of a few pairs of 

 large leaflets borne on a continuation of the leaf-stalk. The lower 

 leaves are often very large and have long stalks, but higher up, 

 in the region of the inflorescence (Fig. i), the smaller leaf-blades 

 are borne directly on the sheath, no stalk being developed. On 



