TURNIP 



373 



part, in popular parlance, being variously termed the 'turnip,' 

 turnip 'bulb' or turnip 'root.' In all cases the amount of 

 hypocotyl is considerable, but the relative proportion of this 

 part of the plant to the true root is not the same in all varieties, 

 and probably varies with the soil and cultivation which the plants 

 receive. 



The swollen fleshy ' root ' of a turnip possesses essentially the 

 same arrangement of tissues as is common in ordinary roots 

 and stems. The relative proportion and composition of each 

 tissue is, however, very different. 



A transverse section (2, Fig. 118) of a turnip 'root' shows an 

 outer layer about ^ of an inch thick, chiefly bast {d) ; within is 

 the wood {a) which forms the main mass of the ' turnip ' ; it is 

 produced by the cambium {c). Almost the whole of the wood 

 consists of thin-walled, unlignified wood-parenchyma, imbedded 

 in which appear radial lines of vessels in small isolated groups. 

 Medullary rays are present, but these are not readily dis- 

 tinguished from the degenerate wood-parenchyma: they form 

 but a comparatively small part of the fleshy ' root.' 



Leaves. — The stem upon which the leaves grow remains very 

 short during the first year : the leaves consequently appear in a 

 rosette-like bunch at the top of the so-called bulb. The first 

 foliage leaves are roundish with irregularly serrate margins, those 

 growing later being pinnatifid or pinnate with a large oval 

 terminal lobe (lyrate). All produced during the first year's 

 growth are grass-green and beset with rough harsh hairs. 



In the second season the terminal bud in the centre of the 

 rosette of radical leaves, develops into a strong erect stem with 

 many branches. The leaves upon the latter are somewhat 

 glaucous and smooth, the upper ones being ovate-lanceolate, 

 sessile, with bases which partially clasp round the stem. 



The ends of the branches and main stem terminate m 

 inflorescences. 



Inflorescence and Flowers. — The turnip inflorescence is a 



