CHAP. III.] 
AND TUBERS. 
49 
seed. There is, however, one important dif¬ 
ference between them ; the seed expends its 
accumulated stock of carbon in giving birth 
to the root, stem, and leaves, after which it 
withers away and disappears ; while the bulb 
or tuber continues to exist during the whole 
life of the plant, and appears to contain a 
reservoir of carbon, which it only parts with 
slowly, and as circumstances may require. 
Though bulbs and tubers have here been 
mentioned as almost synonymous, modern 
botanists make several distinctions between 
them. The tunicated bulbs, such as those 
of the hyacinth and the onion, and the 
squamose bulbs, such as those of the lily, 
they consider to be underground buds while 
tubers such as those of the dahlia, and the 
potatoe, and solid bulbs or corrns, such as 
those of the crocus, they regard as under¬ 
ground stems. 
These distinctions, however, though they 
may be interesting to the botanist and 
vegetable physiologist, are of little or no 
use in practice ; the practical gardener treat¬ 
ing bulbs and tubers exactly alike, and 
planting them as he would sow a seed: that 
E 
