56 THE PHENOMENON OF 



bulbous plants, the narcissus and its allies, the snowdrop, 

 on the one hand, the tulip and onion {Allium) on the 

 other, may furnish examples. Narcissus poeticus, when 

 arrived at a flowering age, annually produces a sheath- 

 like, closed, cataphyllary leaf, and four euphyllary leaves, 

 the last of which, bearing the flower in its axil, is devoid 

 of the embracing sheath of the preceding. As long as 

 no axillary flower is produced, the innermost euphyllary 

 leaf of the annual cycle possesses a sheath. Leucojum 

 vernum, similar in other respects, has only three euphjd- 

 lary leaves, the middle one being that which bears the 

 flower, and is devoid of a sheath ; the third, which has 

 again a sheath, is thus already on the retreat back to 

 the cataphyllary formation.' In Galantlms nivalis the 

 annual cycle is composed of one cataphyllary leaf and 

 two euphyllary leaves, the upper of these two being 

 without the sheath, and with a flower. While in the 

 heart of the bulb of this plant one annual cycle succeeds 

 another in an infinite series, the product of the earlier 

 years dies viw&y, pari passu, at the periphery of the bulb, 

 since not only does one sheath after another dry up and 

 moulder away, but also the base of the axis of the bulb 

 throws ofi" the superannuated part by exfoliation. The 

 old circles of roots are also thrown off, and replaced by 

 new. The tulip displays a difi'erent character. While 

 in the narcissus the flower arises as a lateral sprout, in 

 the tulip the heart of the bulb itself shoots up, after 

 mostly three tubularly closed cataphyllary leaves, into a 

 flower-stem with euphyllary leaves. But before this 

 happens, the development alternates for several years 

 with cataphyllary and euphyllary formations, annually 

 sending above ground only one euphyllary leaf, and then 

 returning to cataphyllary formation in the centre. With 

 this frequently occurs the remarkable case, that, in buds 

 not yet arrived at sufficient maturity to produce flowers, 

 the central bud of the bulb sinks down into a descending 

 spur, formed out of the inclosing base of one of the 



